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Table of Contents First Aid and Safety Precaution ................................................................................................................... 7

First Aid Kit............................................................................................................................... 7

Proper Handling of electrical and electronics components .................................................................... 12

Computer System ....................................................................................................................................... 16

Hardware ............................................................................................................................... 17

Input Devices ................................................................................................................................. 17

Output Devices............................................................................................................................... 22

Storage Devices .............................................................................................................................. 26

Processor ....................................................................................................................................... 33

Software ................................................................................................................................................... 59

DOS ................................................................................................................................................ 64

DOS Command .................................................................................................................. 66

Internal Command ............................................................................................... 81

External Command .............................................................................................. 83

Windows ........................................................................................................................................ 86

Linus/Unix .................................................................................................................................... 100

Basic Computer Components and Peripherals..................................................................................... 108

Monitor ........................................................................................................................................ 111

Types of Monitor ............................................................................................................ 111

Basic Part of Monitor ...................................................................................................... 112

Central Processing Unit ................................................................................................................ 113

Vital parts of CPU ............................................................................................................ 114

Motherboard ..................................................................................................... 115

Types and compatibility ..................................................................................... 116

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Memory ............................................................................................................. 122

Random Access Memory ...................................................................... 125

Types of RAM ........................................................................... 125

Read Only Memory ............................................................................... 126

System Bus ............................................................................................ 128

ISA ............................................................................................ 129

EISA .......................................................................................... 129

PCI ............................................................................................ 130

AGP .......................................................................................... 131

MCA ......................................................................................... 132

USB ........................................................................................... 133

CMOS .................................................................................................... 134

POST ......................................................................................... 136

SETUP ....................................................................................... 137

Chipset .................................................................................................. 139

Northbridge ............................................................................. 139

Southbridge ............................................................................. 143

Network Interface Card ........................................................................ 158

Types and function .................................................................. 158

Processor .............................................................................................. 181

INTEL ........................................................................................ 182

AMD ......................................................................................... 183

Video Cards ........................................................................................... 185

Types and Function .................................................................. 187

Installation ............................................................................... 188

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Power Supply ..................................................................................................... 195

Connectors ......................................................................................................... 200

Troubleshooting Motherboards ........................................................................................................... 204

Symptoms .................................................................................................................................... 208

Diagnosis ...................................................................................................................................... 208

Storage Devices ..................................................................................................................................... 213

Hard Disk Drive ............................................................................................................................ 214

Parts and Types ............................................................................................................... 215

Installation ...................................................................................................................... 215

Jumper Setting ................................................................................................... 219

Partitioning ........................................................................................................ 221

Formatting ......................................................................................................... 223

CD-ROM Drives ............................................................................................................................ 227

Types and Parts ............................................................................................................... 227

Floppy Disk Drive ......................................................................................................................... 229

Types and Parts ............................................................................................................... 230

Printers .................................................................................................................................................. 234

Types of Printer ............................................................................................................................ 234

Dot Matrix ....................................................................................................................... 234

Inkjet ............................................................................................................................... 235

Laser ................................................................................................................................ 235

Installation of Printers ................................................................................................................. 236

Troubleshooting Printer ............................................................................................................... 238

Symptoms and diagnosis ................................................................................................ 241

Mouse .................................................................................................................................................... 245

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Types of Mouse ............................................................................................................................ 245

Trackball .......................................................................................................................... 245

Digital Mouse .................................................................................................................. 245

Installation of Mouse ................................................................................................................... 245

Troubleshooting Mouse ............................................................................................................... 247

Symptoms and Diagnosis ................................................................................................ 248

Software Installation............................................................................................................................. 252

Windows ...................................................................................................................................... 255

System Software and Drivers ....................................................................................................... 260

Networking Basics ................................................................................................................................. 265

Computer Networking ................................................................................................................. 265

Types of Computer Network ........................................................................................... 265

SAN ..................................................................................................................... 265

LAN ..................................................................................................................... 265

MAN ................................................................................................................... 265

WAN ................................................................................................................... 266

Network Devices ............................................................................................................. 266

Modem............................................................................................................... 266

Hub ..................................................................................................................... 267

Switch ................................................................................................................. 268

Repeaters ........................................................................................................... 268

Router ................................................................................................................ 268

Types of Computer Network Topology ........................................................................... 269

Star ..................................................................................................................... 270

Ring .................................................................................................................... 271

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Bus ..................................................................................................................... 271

Mesh .................................................................................................................. 272

Token Ring ......................................................................................................... 273

Network Interface Card Installation ............................................................................................ 273

Cabling ......................................................................................................................................... 275

Categories of Cables ....................................................................................................... 276

Types and Configuration of Cables ................................................................................. 282

Straight Through ................................................................................................ 282

Cross-over .......................................................................................................... 283

Roll-over ............................................................................................................. 284

IP Address Familiarization ............................................................................................................ 285

Classification of IP Address ............................................................................................. 286

Setting up IP Address ...................................................................................................... 287

IP Configuration .................................................................................................................................... 292

Automatic IP Configuration ......................................................................................................... 292

Manual Allocation of IP Address .................................................................................................. 299

Computer Network Configuration ........................................................................................................ 301

Peer-to-Peer Network .................................................................................................................. 301

Client/Server Network ................................................................................................................. 302

Network Troubleshooting ..................................................................................................................... 303

Testing Device ................................................................................................................. 303

LAN Tester .......................................................................................................... 311

PING Commands ................................................................................................ 312

Symptoms and Commands ...................................................................................................

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QUIZZES

1 ............................................................................................................................................................... 15

2 ............................................................................................................................................................... 58

3 ............................................................................................................................................................. 107

4 ............................................................................................................................................................. 157

5 ............................................................................................................................................................. 233

6 ............................................................................................................................................................. 251

7 ............................................................................................................................................................. 264

8 ............................................................................................................................................................. 325

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First Aid Kit

A first aid kit is a collection of supplies and equipment for use in giving first aid, and can

be put together for the purpose by an individual or organization or purchased complete.

There is a wide variation in the contents of first aid kits based on the knowledge and

experience of those putting it together, the differing first aid requirements of the area

where it may be used and variations in legislation or regulation in a given area.

The international standard for first aid kits is that they should be identified with the

ISO graphical symbol for first aid (from ISO 7010) which is an equal white cross on a

green background, although many kits do not comply with this standard, either because

they are put together by an individual or they predate the standards.

Format

First aid kits can be assembled in almost any type of container and this will depend on

whether they are commercially produced or assembled by an individual. Standard kits

often come in durable plastic boxes, fabric pouches or in wall mounted cabinets. The

type of container will vary depending on purpose, and they range in size from wallet

sized through to large rucksacks.

It is recommended that all kits are in a clean, waterproof container to keep the contents

safe and aseptic. Kits should also be checked regularly and restocked if any items are

damaged or are expired out of date.

Appearance

The International Organization for Standardization (ISO) sets a standard for first aid kits

of being green, with a white cross, in order to make them easily recognizable to anyone

requiring first aid.

ISO First Aid Symbol Alternate version of Red Cross Star of Life

the first aid symbol

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CONTENTS

FIRST AID PRECAUTION

1. LOOK around. Is it safe to help? If not, call 9-1-1, have someone else call, or seek medical help. If it is safe to help, stay calm and go to step 2.

2. CHECK for a response.

3. Gently tap the person. Ask, “Are you okay?” Ask loudly. Call the person by name if you know it.

A Pocket mask in its case.

Adhesive bandages are one of the most commonly used

items in a first aid kit.

Plastic Tweezers

Disposable gloves are often found in modern first-aid kits.

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4. If the person responds or moves, attend to his or her problem, as needed. If the person is injured or the problem is serious, call for emergency medical care. Give first aid as needed, until medical help arrives.

5. If the person does not respond or move, begin CPR.

6. PROTECT yourself from hepatitis B virus

and HIV, the virus that causes AIDS. You can get these from an infected person’s blood or other body fluids if they enter your body. These organisms can enter through cuts or breaks in your skin or through the lining of your mouth, nose, and eyes. When you give first aid or do CPR, take these steps, especially if you don’t know the person:

7. Use plastic wrap or a plastic bag that you

can throw away whenever you touch another person’s body fluids, blood, or other objects that may be soiled with his or her blood. If possible, have the person apply pressure to the wound with his or her own hand.

8. Cover the person’s open wounds with dressings, extra gauze, or water proof material.

9. Using a mouth-to-mouth barrier device when you give rescue breaths may or may not protect you from picking up an infection. If you are not willing to give mouth-to-mouth rescue breaths during CPR, do Hands-Only CPR.

Wash your hands with soap and water right after you give first aid. 1. Report every incident in which you are exposed to another person’s blood or

other body fluids to your doctor, local health department, or EMS personnel. Do this within 1 to 2 hours.

2. FIND out if the person has certain medical needs.

3. Ask if he or she has prescribed medicine, such as nitro-glycerine, to take for a

heart condition. Ask where he or she keeps the medicine. Find out how much to give. Ask the person or read the directions on the medicine’s label, if there is one.

4. Ask the person if you can give the medicine to him or her.

5. Look for a medical alert tag to find out about health problems the person has.

6. Find out if the person is allergic to any medicine.

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Safe Lab Procedures (2.1)

This section discusses safety in the lab. Safety guidelines help protect individuals from accidents and injury. They also help to protect equipment from damage. Some of these guidelines are designed to protect the environment from contamination caused by improperly discarded materials.

General Safety (2.1.1.1)

Safe working conditions help prevent injury to people and damage to computer equipment. A safe workspace is clean, organized, and properly lighted. Everyone must understand and follow safety procedures.

Follow the basic safety guidelines to prevent cuts, burns, electrical shock, and damage to eyesight. As a best practice, make sure that a fire extinguisher and first-aid kit are available in case of fire or injury. Poorly placed or unsecured cables can cause tripping hazards in a network installation. Cables should be installed in conduit or cable trays to prevent hazards.

This is a partial list of basic safety precautions to use when working on a computer:

Remove your watch and jewelry and secure loose clothing. Turn off the power and unplug equipment before performing service. Cover sharp edges inside the computer case with tape. Never open a power supply or a CRT monitor. Do not touch areas in printers that are hot or that use high voltage. Know where the fire extinguisher is located and how to use it. Keep food and drinks out of your workspace. Keep your workspace clean and free of clutter. Bend your knees when lifting heavy objects to avoid injuring your back.

Electrical Safety (2.1.1.2)

Follow electrical safety guidelines to prevent electrical fires, injuries, and fatalities in the home and the workplace. Power supplies and CRT monitors contain high voltage.

CAUTION

Do not wear the antistatic wrist strap when repairing power supplies or CRT monitors. Only experienced technicians should attempt to repair power supplies and CRT monitors.

Some printer parts become hot during use, and other parts might contain high voltage. Check the printer manual for the location of high-voltage components. Some

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components retain a high voltage even after the printer is turned off. Make sure that the printer has had time to cool before making the repair.

Electrical devices have certain power requirements. For example, AC adapters are manufactured for specific laptops. Exchanging power cords with a different type of laptop or device may cause damage to both the AC adapter and the laptop.

ELECTRICAL SAFETY There is always a potential danger of electric shock or fire whenever there are outlets, plugs, wiring or connections. In addition to the usual electrical hazards, some labs have high voltage electrical equipment.

Familiarize yourself with the location of Circuit breaker panels in labs.

Maintain an unobstructed access to all electrical panels.

Electrical cords must be secured

Connect to the power source LAST.

Turn off and unplug equipment (instead of relying on interlocks that can fail) before removing the protective cover to replace a part, adjust or troubleshoot.

Do not use an electrical outlet or switch if the protective cover is ajar, cracked or missing

All electrical apparatus must be properly grounded.

Never remove the ground pin of a 3-pronged plug.

Do not run wires over moving or rotating equipment, or on the floor, or string them across walkways from bench to bench as this creates a trip hazard.

DO NOT use electric wires as supports and never pull on live wires.

Ensure that all wires are dry before plugging into circuits. Remove electrical cords from the receptacle by grasping and pulling the plug not

the cord Always pick up and carry portable equipment by the handle or base. Only use DRY hands and stand on a dry surface when using electrical

equipment, plugging in an electric cord, etc. If electrical equipment emits smoke or a burning smell, shut off power

immediately and take it out of service for repair.

Fire Safety (2.1.1.3)

Follow fire safety guidelines to protect lives, structures, and equipment. To avoid an electrical shock and to prevent damage to the computer, turn off and unplug the computer before beginning a repair.

Fire can spread rapidly and be very costly. Proper use of a fire extinguisher can prevent a small fire from getting out of control. When working with computer components, be aware of the possibility of an accidental fire and know how to react. Be alert for odors emitting from computers and electronic devices. When electronic components overheat or short out, they emit a burning odor. If there is a fire, follow these safety procedures:

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Never fight a fire that is out of control or not contained. Always have a planned fire escape route before beginning any work. Get out of the building quickly. Contact emergency services for help. Locate and read the instructions on the fire extinguishers in your workplace

before you have to use them.

Be familiar with the types of fire extinguishers used in your country or region. Each type of fire extinguisher has specific chemicals to fight different types of fires:

Paper, wood, plastics, cardboard Gasoline, kerosene, organic solvents Electrical equipment Combustible metals It is important to know how to use a fire extinguisher. Use the memory aid P-A-S-

S to remember the basic rules of fire extinguisher operation:

P: Pull the pin. A: Aim at the base of the fire, not at the flames. S: Squeeze the lever. S: Sweep the nozzle from side to side.

Proper Handling of electrical and electronic components

Handling Electronic Assemblies

Electrostatic Discharge (ESD) Certain components used in electronic assemblies are sensitive to static electricity and can be damaged by its discharge. Static charges are created when non-conductive materials are separated, such as when plastic bags are picked up or opened, when friction occurs between articles of synthetic clothing, when plastic tapes are dispensed and many other causes. Destructive static charges are induced on nearby conductors, such as human skin, and delivered in the form of sparks passing between conductors, such as when the surface of printed board assembly is touched by a person having a static charge potential. If touched at the right solder joint or conductive pattern, the circuit board assembly can be damaged as the discharge passes through the conductive pattern to a static sensitive component. It is important to note that usually the static damage level for components cannot be felt by humans. (Less than 3,000 volts.)

Electrical Overstress (EOS)

Electrical overstress damage can be caused by generation of unwanted energy; such as spikes, occurring within soldering irons, solder extractors, testing instruments and

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other electrically operated equipment. This equipment must be designed as to prevent unwanted electrical discharges.

ESD/EOS Safe Work Areas

The purpose of an ESD/EOS safe work area is to prevent damage to sensitive components from spikes and static discharges. These areas must be designed and maintained to prevent ESD/EOS damage.

Handling and Storage Methods

1. Circuit board assemblies must always be handled at properly designated work areas.

2. Designated work areas must be checked periodically to ensure their continued protection. Areas of main concern include:

1. Proper grounding methods. 2. Static dissipation of work surfaces. 3. Static dissipation of floor surfaces. 4. Operation of ion blowers and ion air guns.

3. Designated work areas must be kept free of static generating materials including Styrofoam, vinyl, plastic, fabrics and other static generating materials.

4. Work areas must be kept clean and neat. To prevent contamination of circuit board assemblies, there must be no eating or smoking in the work area.

5. When not being worked on, sensitive components and circuit boards must be enclosed in shielded bags or boxes. There are three types of ESD protective enclosure materials including: Static Shielding - Prevents static electricity from passing through the package. Antistatic - Provides antistatic cushioning for electronic assemblies. Static Dissipative - An "over-package" that has enough conductivity to dissipate any static build up.

6. Whenever handling a circuit board assembly the operator must be properly grounded by one of the following:

A. Wearing a wrist strap connected to earth ground. B. Wearing 2 heel grounders and have both feet on a static dissipative floor

surface.

7. Circuit board assemblies should be handled by the edges. Avoid touching the circuits or components. (See Figure 1)

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8. Components should be handled by the edges when possible. Avoid touching the component leads.

9. Hand creams and lotions containing silicone must not be used since they can cause solder ability and epoxy adhesion problems. Lotions specifically formulated to prevent contamination of circuit boards are available.

Stacking of circuit boards and assemblies should be avoided to prevent physical

damage. Special racks and trays are available for handling.

Occupational Health and Safety Procedure (OHS) (written):

1. Be careful with the tools that may cause short circuit.

2. Always full cable connector on the handle and not on the cable itself.

3. Use only rubber shoes when standing on the ground or in a concrete floor.

4. Make sure that the pins are properly aligned when connecting cable connector.

5. Take away any liquid such as mineral water or soft drinks near your working area or

near computers.

6. Contingency measures during workplace accidents, fire and other emergencies are

recognized.

7. Personal protective equipment is correctly used in accordance with organization

OHS procedures and practices.

8. Hazard/risks in the workplace and their corresponding indicators are identified to

minimize or eliminate risk to co-workers, workplace and environment.

9. Take necessary precautions to protect the components of the computer from

damage caused by ESD (Electrostatic Discharge).

10. Hold the components by the edges and do not touch the IC’s.

11. Read and follow instructions on the manual carefully.

12. Do not use excessive force if things don’t quite slip into place.

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Summary:

First Aid Kit - A first aid kit is a collection of supplies and equipment for use in

giving first aid, and can be put together for the purpose by an individual or organization

or purchased complete.

ISO stands for International Organization for Standardization .

We need to secure every time the first aid kit in case of emergency. We have a first aid

for that accident, example is burn.

We need also to know what the safety procedures are before we start our work to avoid

accidents.

Chapter Quiz:

Essay:

1. Briefly discuss what is First Aid Kit.

2. What are the Occupational Health and Safety Procedure.

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What is Computer?

An electronic device which is capable of receiving information (data) and performing a sequence of logical operations in accordance with a predetermined but variable set of procedural instructions (program) to produce a result in the form of information or signals.

A computer is a general purpose device that can be programmed to carry out a set of arithmetic or logical operations automatically. Since a sequence of operations can be readily changed, the computer can solve more than one kind of problem.

Conventionally, a computer consists of at least one processing element, typically a central processing unit (CPU), and some form ofmemory. The processing element carries out arithmetic and logic operations, and a sequencing and control unit can change the order of operations in response to stored information. Peripheral devices allow information to be retrieved from an external source, and the result of operations saved and retrieved.

A computer includes both hardware and software. In general, hardware is the physical aspect of the computer that can be seen, and software is the invisible instructions that control the hardware and make it work. Computer programming consists of writing instructions for computers to perform. You can learn a programming language without knowing computer hardware, but you will be better able to understand the effect of the instructions in the program if you do. This section gives a brief introduction to computer hardware components and their functionality.

A computer consists of the following major hardware components:

Central Processing Unit (CPU)

Memory

Secondary Storage

Input and Output Devices

Computer System

A system of interconnected computers that share a central storage system and

various peripheral devices such as a printers, scanners, or routers. Each computer

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connected to the system can operate independently, but has the ability to communicate

with other external devices and computers.

A complete working computer, Computer systems will include the computer along with

any software and peripheral devices that are necessary to make the computer function.

Every computer system, for example, requires an operating system.

What is Hardware?

The physical, touchable, electronic and mechanical parts of a computer system.

All the Physical parts of a Computer System (the bits that you can see and touch)

Tangible part/ devices of computer.

INPUT DEVICES

What are Input Devices?

Input devices gather data and convert them into electronic form for use by the

computer.

The Physical Parts of a Computer System which allows data to be entered into a

Computer System

Data or instructions entered into memory of computer

Accepts data and instructions from the user or from another computer system.

In computing, an input device is any peripheral (piece of computer hardware equipment) used to provide data and control signals to an information processing system such as a computer or other information appliance. Examples of input devices include keyboards, mouse, scanners, digital cameras and joysticks.

Many input devices can be classified according to:

Modality of input (e.g. mechanical motion, audio, visual, etc.)

the input is discrete (e.g. key presses) or continuous (e.g. a mouse's position, though digitized into a discrete quantity, is fast enough to be considered continuous)

the number of degrees of freedom involved (e.g. two-dimensional traditional mice, or three-dimensional navigators designed for CAD applications)

Pointing devices, which are input devices used to specify a position in space, can further be classified according to:

Whether the input is direct or indirect. With direct input, the input space coincides with the display space, i.e. pointing is done in the space where visual feedback or the pointer appears. Touchscreens and light pens involve direct input. Examples involving indirect input include the mouse and trackball.

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Whether the positional information is absolute (e.g. on a touch screen) or relative (e.g. with a mouse that can be lifted and repositioned)

Direct input is almost necessarily absolute, but indirect input may be either absolute or relative. For example, digitizing graphics tablets that do not have an embedded screen involve indirect input and sense absolute positions and are often run in an absolute input mode, but they may also be set up to simulate a relative input mode like that of a touchpad, where the stylus or puck can be lifted and repositioned.

Input and output devices make up the hardware interface between a computer and a scanner or 6DOF controller.

What are the two types of input?

Data

o Unprocessed text, numbers,

images, audio, and video

Instructions

o Programs

o Commands

o User responses

Examples of Input Devices:

Keyboard

Mouse

Joystick

Scanner

Microphone

Keyboard

Most common and very popular input device is keyboard. The keyboard helps in inputting the data to the computer. The layout of the keyboard is like that of traditional typewriter, although

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there are some additional keys provided for performing some additional functions.

Keyboards are of two sizes 84 keys or 101/102 keys, but now 104 keys or 108 keys keyboard is also available for Windows and Internet.

The keys are following

Sr.

No. Keys Description

1 Typing Keys

These keys include the letter keys (A-Z) and

digits keys (0-9) which generally give same

layout as that of typewriters.

2 Numeric Keypad

It is used to enter numeric data or cursor

movement. Generally, it consists of a set of 17

keys that are laid out in the same configuration

used by most adding machine and calculators.

3 Function Keys

The twelve functions keys are present on the

keyboard. These are arranged in a row along

the top of the keyboard. Each function key has

unique meaning and is used for some specific

purpose.

4 Control keys

These keys provide cursor and screen control.

It includes four directional arrow key. Control

keys also include Home, End, Insert, Delete,

Page Up, Page Down, Control(Ctrl),

Alternate(Alt), Escape(Esc).

5 Special Purpose Keys

Keyboard also contains some special purpose

keys such as Enter, Shift, Caps Lock, Num

Lock, Space bar, Tab, and Print Screen.

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Keyboard Entry – Data is inputted to the computer through a keyboard.

- Keyboard - The first input device developed for the PC. Data is transferred to the

PC over a short cable with a circular 6-pin Mini-din connector that plugs into the

back of the motherboard.

- Direct Entry – A form of input that does not require data to be keyed by someone

sitting at a keyboard. Direct-entry devices create machine-readable data on

paper, or magnetic media, or feed it directly into the computer’s CPU.

There are 3 types of Keyboard:

1. PS2(Violet)

2. Standard

3. USB

3 Parts of Keyboard

1. Alphanumeric

2. Function Key(F1-F10-12)

3. Special Keys

Mouse

Mouse is most popular Pointing device. It is a very famous cursor-control device. It is a small palm size box with a round ball at its base which senses the movement of mouse and sends corresponding signals to CPU on pressing the buttons.

Generally, it has two buttons called left and right button and scroll bar is present at the mid. Mouse can be used to control the position of cursor on screen, but it cannot be used to enter text into the computer.

- Pointing device that fits under palm of hand

Pointing Devices - An input device used to move the pointer (cursor) on screen.

Mouse - The most common 'pointing device' used in PCs. Every mouse has two buttons and most have one or two scroll wheels.

ADVANTAGES

Easy to use

Not very expensive

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Moves the cursor faster than the arrow keys of keyboard.

There are 3 types of Mouse:

1. PS2 (Green)

2. Serial

3. USB

Kinds of Mouse

1. Optical

2. Trackball

Joystick

Joystick is also a pointing device which is used to move cursor position on a monitor screen. It is a stick having a spherical ball at its both lower and upper ends. T he lower spherical ball moves in a socket. T he Joystick can be moved in all four directions.

T he function of joystick is similar to that of a mouse. It is mainly used in Computer Aided Designing (CAD) and playing computer games.

Scanner

- A device that can read text or illustrations printed on paper and translates the

information into a form the computer can use.

- Scanner is an input device, which works more like a photocopy machine. It is used when some information is available on a paper and it is to be transferred to the hard disc of the computer for further manipulation.

- Scanner captures images from the source which are then converted into the digital form that can be stored on the disc. These images can be edited before they are printed.

- Light-sensing device that reads printed text and graphics - Used for image processing, converting paper documents into electronic images

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Different Types of Scanner:

1. Flatbed Scanner

- A scanner, plotter, or other device which keeps paper flat during use.

2. Handheld Scanner (Barcode Reader)

Bar Code Reader is a device used for reading bar coded

data (data in form of light and dark lines). Bar coded data is

generally used in labelling goods, numbering the books, etc.

It may be a hand-held scanner or may be embedded in a

stationary scanner.

Microphone

Microphone is an input device to input sound that is then stored in digital form. The microphone is used for various applications like adding sound to a multimedia presentation or for mixing music.

OUTPUT DEVICE

What are Output Devices?

- An output device is any piece of computer hardware equipment used to communicate the results of data processing carried out by an information processing system (such as a computer) which converts the electronically generated information into human-readable form.

- An output device is any peripheral that receives or displays output from a

computer. The picture shows an inkjet printer, an output device that can make a hard

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copy of anything being displayed on a monitor. Below is a listing of all the different

computer output devices used with a computer.

Display devices

A display device is an output device that visually conveys text, graphics, and video information. Information shown on a display device is called soft copy because the information exists electronically and is displayed for a temporary period of time. Display devices include CRT monitors, LCD monitors and displays, gas plasma monitors, and televisions.

Examples of Output Devices:

Monitor

Printer

Headphones/ Speaker

Projector

Monitors

Monitor commonly called as Visual Display Unit (VDU) is the main output device of a computer. It forms images from tiny dots, called pixels, that are arranged in a rectangular form. The sharpness of the image depends upon the number of the pixels.

There are two kinds of viewing screen used for monitors:

Cathode-Ray Tube (CRT)

Flat-Panel Display

Cathode-Ray Tube (CRT) Monitor

In the CRT, display is made up of small picture elements called pixels for short. The smaller the pixels, the better the image clarity or resolution. It takes more than one illuminated pixel to form whole character, such as the letter 'e' in the word help.

A finite number of characters can be displayed on a screen at once. The screen can be divided into a series of character boxes - fixed location on the screen where a standard character can be placed.

Most screens are capable of displaying 80 characters of data horizontally and 25 lines vertically. There are some disadvantages of CRT:

Large in Size

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High power consumption

Flat-Panel Display Monitor

The flat-panel display refers to a class of video devices that have reduced volume, weight and power requirement compared to the CRT. You can hang them on walls or wear them on your wrists. Current uses for flat-panel displays include calculators, video games, monitors, laptop computer, graphics display.

The flat-panel display are divided into two categories:

Emissive Displays - The emissive displays are devices that convert electrical energy into light. Examples are plasma panel and LED (Light-Emitting Diodes).

Non-Emissive Displays - The Non-emissive displays use optical effects to convert sunlight or light from some other source into graphics patterns. Example is LCD (Liquid-Crystal Device)

Printers

Printer is the most important output device, which is used to print information on paper.

There are two types of printers:

Impact Printers

Non-Impact Printers

Under Impact Printer is Dot-matrix Printer.

Under Non-Impact Printers are Laser Printer and Inkjet Printer.

Speakers

Use to play sound. They may be built into the system

unit or connected with cables. Speakers allow you to

listen to music and hear sound effects from your

computer.

Computer component that produces music, speech,

25

or other sounds

Speakers and headsets are common devices

Projector

A device used to project rays of light, especially an apparatus for projecting slides or film on to a screen.

LCD Projectors- utilize two sheets of polarizing material with a liquid crystal solution between them. An electric current passed through the liquid causes the crystals to align so that light cannot pass through them. Each crystal, therefore, is like a shutter, either allowing light to pass through or blocking the light.

Smart Board

A type display screen that has a touch

sensitive transparent panel covering the

screen which is similar to a touch screen.

What is the difference between an input and output device?

To understand the difference between an input and output

device, you must understand the difference

between input and output. Any information or data that's

entered or sent to the computer to be processed is considered

input and anything that is displayed from the computer is

26

output. Therefore, an input device such as a computer keyboard is capable of having

information sent to the computer, but does not display (output) any information. An

output device such as a computer printer can print information from the computer but

does not send any information (input) to the computer.

STORAGE DEVCE

What are Storage Devices?

Alternatively referred to as storage, storage media,

or storage medium, a storage device is

any hardware device capable of holding information.

There are two storage devices used in computers; a

primary storage device such as computer RAM and

a secondary storage device such as a computer hard

drive. The secondary storage could be

a removable, internal, or external storage. The picture

shows an example of a Drobo, an external secondary storage device.

Without a storage device, your computer would not be able to save any settings or

information and would be considered a dumb terminal. Below, are some additional

examples of storage devices that are used with computers.

Types of computer storage

Floppy diskette

CD-ROM disc

CD-R and CD-RW disc

Cloud storage

DVD-R, DVD+R, DVD-RW, and DVD+RW disc

Jump drive and USB flash drive

Hard drive

Memory card

Memory stick

Tape cassette

Zip diskette

27

Primary Storage

Primary storage is a category of computer storage, often called main memory.

Has three functions:

o Stores all or part of the program that is being executed.

o Stores the operating system programs that manage the operation of the

computer.

o Holds data that the program is using.

Data and program are placed in primary storage before processing, between

processing steps and after processing has ended prior to being returned to

secondary storage or released as output.

Memory

How is memory measured?

o By number of bytes available for storage

Modern primary storage devices include:

o Random access memory (RAM)

It is used for short-term storage of data or program instructions.

RAM is volatile. Its contents will be lost when the computer’s

electric supply is disrupted by a power outage or when the

computer turned off.

o Read-only memory (ROM)

It can only be read from. It cannot be written to. ROM chips come

from the manufacturer with programs already burned in, or stored.

ROM is used in general-purpose computers to store important or

frequently used programs, such as computing routine for

calculating the square roots of numbers.

Term Abbreviation Approximate Size

Kilobyte KB or K 1 thousand bytes

Megabyte MB 1 million bytes

Gigabyte GB 1 billion bytes

Terabyte TB 1 trillion bytes

28

Primary Memory (Main Memory)

Primary memory holds only those data and instructions on which computer is currently working. It has limited capacity and data gets lost when power is switched off.

It is generally made up of semiconductor device. These memories are not as fast as registers. The data and instructions required to be processed earlier reside in main memory. It is divided into two subcategories RAM and ROM.

Characteristic of Main Memory

These are semiconductor memories.

It is known as main memory.

Usually volatile memory.

Data is lost in case power is switched off.

It is working memory of the computer.

Faster than secondary memories.

A computer cannot run without primary memory.

Secondary Memory

This type of memory is also known as external memory or non-volatile. It is slower than main memory. These are used for storing Data/Information permanently.

CPU directly does not access these memories, instead they are accessed via input-output routines. Contents of secondary memories are first transferred to main memory and then CPU can access it. For example, disk, CD-ROM, DVD, etc.

Characteristics of Secondary Memory

These are magnetic and optical memories.

It is known as backup memory.

It is non-volatile memory.

Data is permanently stored even if power is switched off.

It is used for storage of the data in the computer.

Computer may run without secondary memory.

Slower than primary memories.

29

Optical storage devices

CD rom/DVD ROM

Definition : CD Read Only Memory/DVD Read Only Memory

This means when we buy it, it has some data already installed on it and we can’t

remove that data. We can read it, but can’t save on it

Examples are: Musical CD, Film DVD

Advantage

It has a lot of memory on it

Disadvantage

A data can be installed on it one time only.

CD R/DVD R

An empty CD/DVD disk

Advantages

It is small and portable.

It is very cheap to produce.

Fairly fast to access data.

Disadvantages

Data can be stored 1 time only.

It is easy to break or scratched.

CD RW/DVD RW

Advantages

CD 2. DVD

30

It has enough memory in it.

The data can be stored as much time as you want.

It is small and portable.

Fairly fast to access data.

Disadvantages

DVDs do not work in CD drives.

There is no single standard of DVD.

They can be easily damaged by breaking or scratching.

DVD RAM

DVD Random-Access Memory

Advantages

Long life (about 30 years without damaging).

Can be rewritten about 100000 times.

Has write-protect tabs to prevent accidental deletion when used in a cartridge.

Disadvantages

Less compatibility than DVD+RW and DVD-RW, despite predating both formats

(as noted above).

DVD-RAM media is more expensive than other types of DVD.

HD DVD

High Definition/Density DVD

Advantages

Cheap considering the picture quality produced by HD-DVD and the list of movie

studios.

Sounds good.

Backwards compatibility included.

Disadvantages

Xbox 360 version features no HDMI.

Films are not cheap.

31

Blu-ray

Advantages

Huge storage capacity.

Backwards compatibility.

Keep on burning.

Quality support.

Disadvantages

High cost.

Solid state backing storage

Advantages

Smallest form of memory used as removable storage.

More robust than other forms of storage.

Can be easily written to and updated.

Small and comfortable.

Disadvantages

More expensive than other forms.

Easy to lost.

Memory sticks/pen drives

Advantages

Used to transport files and backup data from computer to computer.

Can store up to a lot of Gigabytes.

Disadvantages

Can be easily lost.

Flash memory cards

Advantages

They are compact and portable.

32

They hold a lot of data.

They are reliable.

Disadvantages

At the moment, the cost per megabyte of storage is more expensive than floppy

disks, CDs or DVDs.

They can be easily lost.

The metal part which is inserted into the USB port can be snapped off if they are

handled roughly.

Magnetic Tape

Magnetic tape is an older storage technology that still used for secondary storage of

large volumes of information.

The principle advantages

Its inexpensiveness, its relative stability and its ability to store very large

quantities of information.

The disadvantages

Its sequentially stored data and its relative slowness compared to the speed

of secondary storage media.

Tape

What is tape?

- Magnetically coated plastic ribbon capable of storing large amounts of data at

low cost.

- Primarily used for backup

PC Cards

What is a PC Card?

- Adds capabilities to computer

- Credit-card-sized device commonly used in notebook computers

33

PROCESSOR

What is Processor?

- The CPU is an example of a processor. It has the same important as the brain to

human being.

- The processor or Central Processing Unit is the brain of the computer

- The performance of the processor is measured in Giga Hertz (GHz)

- We send programs to the processor to get the computer to do something

A processor is the logic circuitry that responds to and processes the basic instructions

that drives a computer.

The term processor has generally replaced the term central processing unit (CPU). The

processor in a personal computer or embedded in small devices is often called a

microprocessor.

A central processing unit (CPU) (formerly also referred to as a central processor unit) is the hardware within a computer that carries out theinstructions of a computer program by performing the basic arithmetical, logical, andinput/output operations of the system. The term has been in use in the computer industry at least since the early 1960s. The form, design, and implementation of CPUs have changed over the course of their history, but their fundamental operation remains much the same.

A computer can have more than one CPU; this is called multiprocessing. All modern CPUs are microprocessors, meaning contained on a single chip. Some integrated circuits (ICs) can contain multiple CPUs on a single chip; those ICs are called multi-core processors. An IC containing a CPU can also contain peripheral devices, and other components of a computer system; this is called a system on a chip (SoC).

Two typical components of a CPU are the arithmetic logic unit (ALU), which performs arithmetic and logical operations, and the control unit (CU), which extracts instructions from memory and decodes and executes them, calling on the ALU when necessary.

Not all computational systems rely on a central processing unit. An array processor or vector processor has multiple parallel computing elements, with no one unit considered the "center". In the distributed computing model, problems are solved by a distributed interconnected set of processors.

Kinds of Microprocessor

INTEL

34

AMD

MOTOROLA/ARM

INTEL

If there was a single semiconductor chip maker the average consumer is aware of it would likely be Intel. If not for the famous Intel "chime" as heard in many television commercials throughout the years then definitely for the fact that it would be difficult not to encounter its technologies in some form whether at work, school or otherwise. Intel is the premier chip maker for personal computers—companies such as Apple, Dell, HP, Samsung, Sony have product lines that depend on the processors that Intel produces. Intel's processors generally offer the best performance for all-around usage. This has been especially the case the last several years with the introduction and evolution of Intel's Core series product line. Currently, Intel's flagship consumer product line consists of mobile and desktop-grade Core i3, Core i5 and Core i7 processors now in their second generation (dubbed "Sandy Bridge"). The third and latest generation of these processors (dubbed "Ivy Bridge") began to roll out for release late April 2012. The biggest difference between these two generations amounts to a moderate improvement in all-around computing performance but a substantial improvement in integrated graphics performance. Another significant feature Ivy Bridge adds is native USB 3.0 support, overtaking USB 2.0.

Intel Comparison Table

Recommend

ed For

Last

Generatio

n

Released

(Codenam

e)

Numb

er of

Cores

Notable

Features

Additiona

l Product

Informati

on

Product

Commentary

Core i7

Enthusiasts,

Superior All-

Around

Performance

, Multi-

tasking,

Multimedia

Creation,

2012 ("Ivy Bridge") and upcoming

2, 4

(1) Hyper-Threading (2) Turbo Boost (3) QuickPath InterConnect (4) Tri-

Intel

The Intel

Core i7

represents

the

company's

most feature

robust

processor

35

Advanced

Productivity

and

Advanced

3D Graphics

Gate (3D) Transistors (5) Intel HD Graphics (6) 64-bit

offering.

They are

Intel's

flagship

series of

processor,

achieving

the greatest

levels of

relative

performance

. As an

excellent all-

around

processor,

the i7 is

ideal for

enthusiasts,

gamers,

power users

and content

creators

alike. They

are available

for both

desktop and

notebook

platforms.

The current

generation

of i7 (as well

as i3 and i5)

processors

is Ivy Bridge

as of Mid-

2012.

Core i5

All-Around

Performance

, Multi-

2012 ("Ivy Bridge") and

2, 4 (1) Hyper-Threading (on i5

Intel

The Intel

Core i5 is a

class of

36

tasking,

Advanced

Producivity,

Multimedia,

Advanced

3D Graphics

upcoming Mobile Dual-Core only, not available on Quad-Core desktop version) (2) Turbo Boost (3) QuickPath InterConnect (4) Tri-Gate (3D) Transistors (5) Intel HD Graphics (6) 64-bit

high-

performance

processor

just a notch

beneath the

i7. Though

they

generally

possess

same

features as

the i7 with

some

exceptions

(see

Features),

they have

less cache

(L3) memory

which

amounts to

similar, but

lesser all-

around

performance

. Like the i7

and i3, the i5

features

Intel's high

performance

integrated

graphics in

the HD

3000/4000.

Most users

will find the

general level

of

perfomance

offered by

37

the i5 to be

an attractive

option

compared to

a more

expensive

i7-equipped

system.

Core i3

Productivity,

Multi-

tasking,

Basic

Graphics,

Multimedia

2012 ("Ivy Bridge") and upcoming

2, 4

(1) Hyper-Threading (2) QuickPath InterConnect (3) Tri-Gate (3D) Transistors (4) Intel HD Graphics 3000 (5) 64-bit

Intel

The Intel

Core i3

processor is

the closest

successor to

the now out-

of-

production

Core2Duo

processor.

The most

significant

differences

between the

i3 and i5/i7

is the lack of

Turbo Boost

and less

cache (L3)

memory.

The i3 offers

moderate

all-around

performance

and is often

found in

budget-

oriented

systems.

38

Pentium

(Post-2009)

Productivity,

E-mail, and

Web

Browsing,

Photos and

Music

2011

("Sandy

Bridge")

2

Hyper-

Threading

(however,

most

currently

do not

support

this

feature)

Intel

The Intel

Pentium as

a product

line had built

a strong

reputation

with

consumers

in the 90's

through the

early 2000s

with the

Pentium

I/II/III/4

series.

Formerly a

flagship line

of processor,

the Pentium

is currently

in production

as a budget-

oriented

option just

above the

Celeron in

terms of

relative

performance

. The most

recent

iteration of

the Pentium

takes some

architectural

cues from

the Core i

series with

the 2011

Pentium

39

based on the

Sandy

Bridge,

offering

performance

suitable for

most basic

tasks.

Celeron

(Post-2010)

Productivity,

E-mail, and

Web

Browsing,

Photos and

Music

2011

("Sandy

Bridge")

2 64-bit Intel

Throughout

its many

iterations,

the Intel

Celeron has

occupied the

lower end of

the

processor

market in

terms of

both price

and

performance

. Updates to

the Celeron

based on

current

generation

architecture

have been

made to

keep the

processor

relevant.

The

improvement

s are

enough such

that they

allow for

40

running

current

productivity

packages

and web

applications.

They are

best

considered

for an entry-

level system.

Atom

Basic

Productivity,

E-mail, and

Web

Browsing

2012

("Cedar

Trail") and

upcoming

1, 2

(1) Hyper-

Threading

(2) 64-bit

Intel

The Intel

Atom

belongs

almost

exclusively

to a class of

personal

computers

known as

netbooks

(nettops and

tablets are

the lesser

common

instances).

The Atom is

focused not

so much on

performance

as it is on

reducing

power

consumption

. As a result,

many

netbooks

offer

excellent

41

battery life at

the cost of

being unable

to run more

sophisticate

d

applications

beyond web

browsing

and word

processing.

Generally

speaking,

netbook

processors

such as the

Atom do not

see

substantial

performance

gains with

subsequent

generations.

Retiring/Retir

ed Product

Lines

Core 2 Duo

& Core 2

Quad

Multi-tasking, Productivity and Multimedia

2008 2, 4 64-Bit

Intel

- Core 2

Duo

- Core 2

Quad

Though the

Core 2 Duo

and Core 2

Quad

processors

are still in

production,

the platform

has been

succeeded

by the Core i

Series since

42

late 2008.

Despite this,

these

processors

are still very

servicable

providing

adequete

levels of

performance

for

multitasking

to varying

levels of

multimedia

creation and

productivity

applications.

Core

Solo/Core

Duo/Centrino

& Celeron

(Pre-2010)

Basic

Productivity,

E-mail, and

Web

Browsing

2006 1, 2 32-bit N/A

The Core

Duo/Duo

Centrino

processors

preceeded

both the

Core2 and

Core i series

of processor.

Generally do

not

recommend

running

current

software for

optimal use;

consideratio

n of an

upgrade

path is

recommend

43

ed soon.

Pentium III &

Pentium 4

Legacy

software and

operating

system

Late

90s/Early

2000s

1

Pentium 4:

mostly 32-

bit later

versions

64-bit,

w/Hyper-

Threading

N/A

An upgrade

path is

highly

recommend

ed;

Usefulness

is relagated

to doing

basic tasks

such as

running

older

versions of

Microsoft

Office or

browsing

webpages

absent of the

latest media

or plugins

such as

Flash or

Java.

AMD

Though not considered the behemoth in the personal computing space as Intel, AMD is a decisive runner-up—and arguably the only true competitor Intel has in this domain. After spending much of the early to middle 2000's as being the performance and value leader with their Athlon 64 line of personal computing processors, AMD—unable to mimic this success in more recent years, has shifted their focus towards both enthusiast and budget-oriented system configurations. As a result, AMD is considered to be a viable alternative to Intel. Their current offerings are flanked by the Phenom series processors and Fusion APU processors. The Fusion APU (AMD A-Series) is a relatively new platform (as of 2011 and ongoing) that attempts to merge high-end graphical capabilities on the same chip as the processor. This means if your work or play requires a powerful graphics card, then AMD can potentially offer a cost effective alternative.

44

AMD Comparison Table

Recommend

ed For

Last

Generatio

n

Released

(Codena

me)

Numb

er of

Cores

Notable

Features

Additional

Product

Informatio

n

Product

Commenta

ry

FX

Desktop

Enthusiasts,

All-Around

High

Performance

2012

("Bulldoz

er") and

upcoming

4, 6, 8

(1)

HyperTransp

ort

(2) Integrated

DRAM

Controller

with AMD

Memory

Optimizer

(2) AMD

Turbo CORE

(3) AMD

Virtualization

(4) AMD

PowerNow!

(Cool'n'Quiet)

(1) AMD

(2)

Architectu

ral

Features

Available

exclusively

on desktop

platforms,

AMD FX

targets

custom

builders

and

enthusiasts

. This is a

processor

that far

surpasses

the needs

of the

average

user.

However,

given the

amount of

performanc

e it

provides

combined

with the

relative low

cost, it

becomes

45

an

attractive

option for

budget

custom PC

builds. The

FX along

with the A-

Series,

represent

AMD's

current

flagship

products

and later

releases

within

these

product

lines are

planned.

A-Series

(Fusion)

A4: Basic

All-Around

Use/Producti

vity, Casual

Gaming

A6, A8: All-

Around

Performance

, Multimedia,

Advanced

3D Graphics

2012

("Trinity")

and

upcoming

A4: 2 A6, A8: 4

DirectX 11

Capable

Graphics

(1) AMD

(2) Noteb

ook

Features

The AMD

A-Series

(AMD

Fusion) are

a type of

chip that

merges the

CPU with a

high-

performanc

e GPU

(graphics

processing

unit)

resulting in

a versatile

system that

is very

46

power

efficient.

They are

available in

desktops,

laptops and

most

recently,

ultrabooks.

Where the

A4 APU is

found in

less

expensive,

entry level

systems,

the A6 and

A8 are

more

suited for

all-around

use

w/advance

d graphics

application

s (such as

gaming or

3D

modeling).

In May

2012, AMD

released

the next

generation

of Fusion

A-Series

processors

known as

"Trinity",

these

47

processors

promise

much

greater

graphical

and

general

purpose

performanc

e. AMD

has aligned

Trinity as

an answer

to Intel's

Ivy Bridge.

Phenom II

Advanced

Productivity,

HD Video,

3D Graphics,

Photos and

Music

2010 2, 3,

4, 6

(1)

HyperTransp

ort™

(2) Integrated

DRAM

Controller

with AMD

Memory

Optimizer

(3) AMD

Turbo CORE

(4) AMD

PowerNow!

(Cool'n'Quiet)

(5) AMD

CoolCore!

(1) AMD (2) Key Architectural Features

The AMD

Phenom II

is primarily

a class of

high-

performanc

e desktop

processor.I

n 2010,

AMD

claimed to

be the first

in the

industry to

offer a

consumer

class six-

core

processor

though the

X6. Mobile

variants of

the

Phenom II

48

were

introduced

as well, but

not in the

six-core

flavor.

Though

new

generation

s of this

product line

are no

longer in

the works,

this line of

processor

is still sold

as a low-

cost,

budget-

oriented

option for

custom

system

builds. The

performanc

e of this

processor

is more

than

enough for

everyday

usage and

productivity

.

Athlon II

Basic Multi-tasking, Productivity and

2011 and upcoming

2, 3, 4 (1) AMD

Virtualization

(2) AMD

(1) AMD

(2) Key

Architectu

The Athlon II is a relatively recent

49

Multimedia Applications

PowerNow!

(Cool'n'Quiet)

(3) AMD

CoolCore!

ral

Features

processor taking design cues from the Phenom II. Unlike the Athlon Classic, is still in production and far more suited to current productivity applications such as Microsoft Office as well as multitasking and multimedia applcations. It is found in both laptops and desktops as a reasonably-powered, cost-effective option.

Turion II

Productivity,

Photos, and

Music

2010 1, 2

(1)

HyperTransp

ort

(2) 64-bit

AMD

The Turion

II is a

processor

based from

the same

architectur

e in the

Phenom II

and Athlon

50

II. It was

introduced

as a

competitor

to Intel's

Core 2

Duo. As a

result, its

performanc

e should be

very

suitable for

productivity

software.

They

designed

with power

efficiency

in mind and

is found

primarily in

notebook

configuratio

ns.

Sempron

Basic

Productivity,

E-mail, and

Web

Browsing

2010 1, 2

(1)

HyperTransp

ort

(2) 64-bit

AMD

The

Sempron is

the AMD

analogue

to the Intel

Celeron. It

offers very

basic levels

of

performanc

e and is

updated

every so

often so as

to offer an

51

inexpensiv

e option

capable of

running

recent

versions of

productivity

software

such as

Office 2010

as well as

web

application

s.

Retiring/Reti

red Product

Lines

Phenom

Multi-tasking,

HD Video,

Basic

Graphics

2008 2, 3, 4

(1) HyperTransport (2) AMD PowerNow! (Cool'n'Quiet) (3) AMD CoolCore!

AMD

The AMD

Phenom

processor

preceded

the Phenon

II. Though

the

processor

is no longer

in

production,

it is

generally

considered

lower-

middle

range in

performanc

e; suitable

for multi-

tasking and

52

more than

casual use.

The

Phenom

was

available

only for

desktop

platforms.

Athlon

(Classic)

Web Browsing, E-mail

Not In

productio

n (1999-

2005)

1, 2 32-bit or 64-

bit N/A

Formerly

known as

just the

Athlon, the

Athlon

Classic has

not been in

production

since 2005.

The kind of

performanc

e is

extremely

limited for

today's

application

s and is

recommen

ded for

only the

most basic

of uses.

Generally,

a complete

system

upgrade

from this

processor

range

would be

53

advisable if

your needs

fall beyond

web

browsing

and e-mail

tasks.

MOTOROLA/ARM

The increased need for mobile productivity and entertainment has given rise to a relatively new class of devices: smartphones and tablets. ARM is well-known for the design of mobile, power-efficient processor designs. In recent years it has seen its technology used in the products of many prominent electronics companies. Apple's A4/A5/A5X, Nvidia's Tegra, Samsung's Exynos and Texas Instruments' OMAP products all integrate ARM processors into what is known as a system-on-a-chip (SoC). SoCs merge many of the essential components of a computer (such as the CPU, RAM, ROM etc.) on a single chip which allows devices that utilize them to be lightweight and compact. These SoCs have gone on to be implemented in blockbuster products such as Apple's iPhone and iPad or Samsung's series of Galaxy phones. ARM's presence as the CPU and architecture of choice on many mobile devices cannot be understated as estimates put their numbers in the billions.

Companies Utilizing ARM Architecture

System-On-

a-Chip (SoC)

Notable Product(s)

Containing

Type of

ARM

Processor

Number

of

Cores

Additional

Product

Information

Apple

A4

iPhone 4, iPod Touch

(4th Gen), iPad (1st

Gen), AppleTV (2nd

Gen)

Cortex-A8 1

Apple

A5 iPhone 4S, iPad 2,

AppleTV (3rd Gen) Cortex-A9 2

54

A5X iPad (3rd Gen, Retina

Display) Cortex-A9 2

Samsung

Exynos 3 Single

Samsung Galaxy S, Samsung Galaxy Nexus S,

Cortex-A8 1

Samsung

Exynos 4

Dual

Samsung Galaxy SII,

Samsung Galaxy Note

(International)

Cortex-A9 2

Exynos 4

Quad Samsung Galaxy SIII Cortex-A9 4

Exynos 5

Dual N/A

Cortex-

A15 2

Nvidia

Tegra Microsoft Zune HD ARM11 1

Nvidia

Tegra 2

ASUS Eee Pad

Transformer, Samsung

Galaxy Tab 10.1,

Motorola Xoom, Dell

Streak 7 & Pro, Sony

Tablet S

Cortex-A9 2

Tegra 3

ASUS Transformer

Pad 300, ASUS Nexus

7, Acer Iconia Tab

A510 & A700, HTC

One X

Cortex-A9 4

Qualcomm

Snapdragon

S2 Nokia Lumia 900 N/A 1

Qualcomm Snapdragon

S3

Galaxy Note LTE

(AT&T), HP TouchPad N/A 2

Snapdragon Samsung Galaxy SIII N/A 2, 4

55

S4 LTE, HTC EVO 4G

LTE

Texas

Instruments

OMAP 3 Barnes and Noble

Nook Color Cortex-A8 1

Texas

Instruments OMAP 4

Amazon Kindle Fire,

Samsung Galaxy Tab

2, Blackberry

Playbook, Samsung

Galaxy Nexus, Barnes

and Noble Nook Tablet

Cortex-A9 2

OMAP 5 N/A Cortex-

A15 2

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Summary:

Computer

- An electronic device which is capable of receiving information (data) and performing a sequence of logical operations in accordance with a predetermined but variable set of procedural instructions (program) to produce a result in the form of information or signals.

Computer System

- A computer system is the one that is able to take a set of inputs, process them

and create a set of outputs. This is done by the combination of hardware and software.

Hardware

- It is the collection of physical elements that constitutes a computer system.

Computer hardware refers to the physical parts or components of a computer such as

the monitor, mouse, keyboard, computer data storage, hard drive disk (HDD), system

unit (graphic cards, sound cards, memory, motherboard and chips), etc. all of which are

physical objects that can be touched. In contrast, software is instructions that can be

stored and run by hardware.

Input Devices

- Convert data and instructions into electronic form for input into the computer.

o Examples: Mouse, Keyboard, Scanner, Microphone.

Output Devices

- Convert electronic data produced by the computer system and display them in a

form that people can understand.

o Examples: Monitor, Speaker, Projector, Printer

Storage Device

- Information and documents are stored in computer storage so that it can be

retrieved whenever they are needed later on.

- Computer storage is the holding of data in an electromagnetic form for access by

a computer processor.

o Examples: HDD, CD, DVD, Memory Cards, Etc.

Processor

- Also known as Central Processing Unit (CPU) or Microprocessor.

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- Interprets and carries out basic instructions that operate a computer

- It is the Brain of Computer.

o Examples of Processors

INTEL - used for office suite

AMD - used for gaming.

ARM /Motorola - for mobile use.

Intel

- Pentium I

- Pentium II

- Pentium III

- Pentium IV

- Core2Duo

- Dual Core

- Quad Core

- I3

- I5

- I7

AMD

- Duron

- Sempron

- Athlon

- Phenom

- AM2

- AM3

ARM /Motorola

- Mobile Devices

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CHAPTER QUIZ!

Definition of Terms:

1. Hardware

2. Output Device

3. Computer

4. Central Processing Unit

5. Input Device

6. Storage Device

7. Computer System

Enumeration:

8.

9. Give at least 3 example of Output device.

10.

11.

12. Give at least 2 example of Input Device.

13.

14. Kinds of Microprocessor

15.

16.

17. Give at least 2 example of Storage device.

18.

19. Differentiate Input Devices and Output Devices

20.

***GOOD LUCK!***

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Computer software

Computer software (often called just software) is made of one or more computer programs. Sometimes it means one specific program, or it can mean all the software on a computer, including the applications and the operating system. Applications are programs that do a specific thing, such as a game or a word processor. The operating system (Mac OS, Windows 7, Windows XP, Linux, etc) is software that helps the applications run, and controls the display and the keyboard.

The word software was first used in the late 1960s to show the difference from computer hardware, which are the parts of a machine that can be seen and touched. Software is the instructions that the computer follows. Before compact discs (CDs) or Internet downloads, software came on "soft media" like paper punch cards, magnetic discs or magnetic tape.

The word firmware is sometimes used to describe a style of software that is made special for a particular type of computer (or other electronic device) and is usually stored on a Flash memory or ROM chip in the computer. Firmware usually refers to a piece of software that directly controls a piece of hardware, for example the firmware for a CD drive or the firmware for a modem.

Software

Software is a program that enables a computer to perform a specific task, as opposed to the physical components of the system (hardware).

Sometimes abbreviated as SW and S/W, software is a collection of instructions that

enable the user to interact with a computer or have it perform specific tasks for them.

Without software, computers would be useless. For example, without your

Internet browser software you would be unable to surf the Internet or read this page and

without a software operating system the browser would not be able to run on your

computer. In the picture is Microsoft Excel, an example of a software program.

Computer software, or simply software, also known as computer programs, is the non-

tangible component of computers. It represents the set of programs that govern the

operation of a computer system and make the hardware run. Computer software

contrasts with computer hardware, which is the physical component of computers.

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Computer hardware and software require each other and neither can be realistically

used without the other.

Computer software includes all computer programs regardless of their architecture; for

example, executable files, libraries and scripts are computer software. Yet, it shares

their mutual properties: software consists of clearly defined instructions that upon

execution, instructs hardware to perform the tasks for which it is designed. Software is

stored in computer memory and cannot be touched, just as a 3D model shown in an

illustration cannot be touched.

At the lowest level, executable code consists of machine language instructions specific

to an individual processor – typically a central processing unit (CPU). A machine

language consists of groups of binary values signifying processor instructions that

change the state of the computer from its preceding state. For example, an instruction

may change the value stored in a particular storage location inside the computer – an

effect that is not directly observable to the user. An instruction may also (indirectly)

cause something to appear on a display of the computer system – a state change which

should be visible to the user. The processor carries out the instructions in the order they

are provided, unless it is instructed to "jump" to a different instruction, or interrupted.

Software is usually written in high-level programming languages that are easier and

more efficient for humans to use (closer to natural language) than machine

language. High-level languages are compiled or interpreted into machine language

object code. Software may also be written in a low-level assembly language, essentially,

a vaguely mnemonic representation of a machine language using a natural language

alphabet. Assembly language is converted into object code via an assembler.

Categories of Computer Software

Software is often divided into two categories.

Systems software includes the operating system and all the utilities that enable the

computer to function. Applications software includes programs that do real work for

users. For example, word processors, spreadsheets, and database management

systems fall under the category of applications software.

Computer software can be put into categories based on common function, type, or field of use. There are three broad classifications:

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Application software is the general designation of computer programs for performing user tasks. Application software may be general purpose (word processing, web browsers, ...) or have a specific purpose (accounting, truck scheduling, ...). Application software contrast with system software.

System software is a generic term referring to the computer programs used to start and run computer systems and networks.

Computer programming tools, such as compilers and linkers, are used to translate and combine computer program source code and libraries into executable RAMs (programs that will belong to one of the three said categories).

Types of software

Software components of a computer system have no physical presence, they are stored in digital form within computer memory. There are different categories of software, including system software, utilities and applications software. Software can also be described as being either generic or bespoke.

System software is the software used to manage and control the hardware components and which allow interaction between the hardware and the other types of software. The most obvious type of system software is the computer's operating system but device drivers are also included within this category.

Utility software is software such as anti-virus software, firewalls, disk defragmenters and so on which helps to maintain and protect the computer system but does not directly interface with the hardware.

Applications software (also known as 'apps') are designed to allow the user of the system complete a specific task or set of tasks. They include programs such as web browsers, office software, games and so on. They are usually the reason you bought the computer system in the first place and aren't concerned with the management or maintenance of the system itself.

Any individual software package, whichever of the above types it falls into, can be either generic (or 'off-the-shelf') or it can be bespoke (custom-built). Generic software is mass produced with the intention that it will be used by a wide variety of different users in a range of different situations. Bespoke software is created for a specific purpose which will be used in a known environment.

Often generic software is used when there is a package available that meets the needs of the user. Because it is used by many more people the cost of creating it is spread over a greater number of people or organisations and so the cost to the individual is much lower. It also has the advantage that it is available immediately there's no waiting time involved while the software package is designed, created and tested. Bespoke

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software has the advantage that it can be tailor made to exact specifications but it significantly more expensive and will take time to create.

Examples of Computer Software

1. Application Software o Application software o Free application software o Astrology software o Business software o Chemical engineering software o Software for children o Communication software o Computer-aided manufacturing software o Data management software o Desktop widgets o Editing software o Educational software o Entertainment software o Genealogy software o Government software o Graphics software o Industrial software o Knowledge representation software o Language software o Legal software o Library and information science software o Multimedia software o Music software o Personal information managers o Computer programming tools o Religious software o Science software o Simulation software o Spreadsheet software o Stagecraft software o Application software suites o Transport software o Digital typography o Video games o Video software o Word processors o Workflow software

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2. System Software o System software o Free system software o Boot loaders o Compatibility layers o Device drivers o Firmware o Graphical user interfaces o Middleware o Operating systems o Utility software o Windowing systems

3. Development Software o Computer programming tools o OS X programming tools o Bug and issue tracking software o Build automation o Code navigation tools o Code search engines o Compilers o Compiling tools o Computer-aided software engineering tools o Data modeling tools o Debuggers o Desktop database application development tools o Disassemblers o Discontinued development tools o Documentation generators o Text editors o EXE packers o Formal methods tools o Free computer programming tools o Integrated development environments o Java development tools o JavaScript programming tools o Linux programming tools o Software-localization tools o Microsoft development tools o Mobile software programming tools o Profilers o Programming language implementation o Programming tools for Windows o Revision control systems o RISC OS programming tools

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o Software testing tools o Static program analysis tools o UML tools o Unix programming tools o User interface builders o Web development software o Computer programming tool stubs

DISK OPERATING SYSTEM (DOS)

What is Disk Operating System (DOS)

- Disk Operating System (specifically) and disk operating system (generically),

most often reveal themselves in abbreviated form as DOS, refer to an operating

system software used in most computers that provides the abstraction and

management of secondary storage devices and the information on them (e.g., file

systems for organizing files of all sorts). Such software is referred to as a disk operating

system when the storage devices it manages are made of rotating platters, such

as floppy disks or hard disks.

In the early days of microcomputers, computer memory space was often limited, so the

disk operating system was an extension of the operating system. This component was

only loaded if needed. Otherwise, disk access would be limited to low-level operations

such as reading and writing disks at the sector-level.

In some cases, the disk operating system component (or even the operating system)

was known as DOS.

Sometimes, a disk operating system can refer to the entire operating system if it is

loaded off a disk and supports the abstraction and management of disk devices.

Examples include DOS/360. On the PC compatible platform, an entire family of

operating systems was called DOS.

- DOS, short for Disk Operating System, is an acronym for several closely related operating systems that dominated the IBM PC compatible market between 1981 and 1995, or until about 2000 including the partially DOS-based Microsoft Windows versions 95, 98, and Millennium Edition.

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Related systems include MS-DOS, PC DOS, DR-DOS, Free DOS, ROM-DOS, and PTS-DOS.

In spite of the common usage, none of these systems were simply named "DOS" (a name given only to an unrelated IBM mainframe operating system in the 1960s). A number of unrelated, non-x86microcomputer disk operating systems had "DOS" in their name, and are often referred to simply as "DOS" when discussing machines that use them (e.g. Amiga DOS, AMSDOS, ANDOS, Apple DOS, Atari DOS, Commodore DOS, CSI-DOS, ProDOS, and TRS-DOS). While providing many of the same operating system functions for their respective computer systems, programs running under any one of these operating systems would not run under others.

- Short for Microsoft Disk operating system, MS-DOS is a non-graphical command

line operating system derived from 86-DOS that was created for IBM compatible

computers. MS-DOS originally written by Tim Paterson and introduced by Microsoft in

August 1981 and was last updated in 1994 when MS-DOS 6.22 was released. MS-DOS

allows the user to navigate, open, and otherwise manipulate files on their computer from

a command line instead of a GUI like Windows.

Today, MS-DOS is no longer used; however, the command shell, more commonly

known as the Windows command line is still used by many users. The picture to the

right, is an example of what an MS-DOS window more appropriately referred to as the

Windows command line looks like running under Microsoft Windows.

Most computer users are only familiar with how to navigate Microsoft Windows using

the mouse. Unlike Windows, MS-DOS is a command-line and is navigated by using MS-

DOS commands. For example, if you wanted to see all the files in a folder in Windows

you would double-click the folder to open the folder in Windows Explorer. In MS-DOS,

to view that same folder you would navigate to the folder using the cd command and

then list the files in that folder using the dir command.

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Disk operating systems

A disk operating system is an operating system component that deals with high-level

disk-IO such as providing the abstraction of a file system resident on a disk storage

system (made up of hard disks and/or floppy disk drives).

Disk Operating System was often abbreviated to the three-letter acronym DOS (not to

be confused with the DOS family of disk operating systems for x86 compatible or

even IBM PC compatible platforms). The use of "DOS" as a suffix of operating system

names was most common in the era when floppy disk drives were the predominant

secondary storage technology, and command line interfaces the predominant OS user

interface. With a few exceptions, this mostly pertained to home-/personal computers of

the 1970s and 80s.

DOS Commands

A Complete List of MS-DOS Commands

DOS commands are the commands available in MS-DOS that are used to interact with the operating system. Unlike in Windows, DOS commands are the primary way in which you use the MS-DOS operating system.

Below is a complete list of the nearly 100 MS-DOS commands, commonly referred to as simply DOS commands, available as of MS-DOS 6.22:

1. Append o The append command can be used by programs to open files in another

directory as if they were located in the current directory.

2. Attrib o The attrib command is used to change the attributes of a single file or a

directory.

3. Break o The break command sets or clears extended CTRL+C checking.

4. Call o The call command is used to run a script or batch program from within

another script or batch program. o The call command has no effect outside of a script or batch file. In other

words, running the call command at the DOS prompt will do nothing.

5. Cd

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o The cd command is the shorthand version of the chdir command.

6. Chcp o The chcp command displays or configures the active code page number.

7. Chdir o The chdir command is used to display the drive letter and folder that you

are currently in. Chdir can also be used to change the drive and/or directory that you want to work in.

8. Chkdsk o The chkdsk command, often referred to as check disk, is used to identify

and correct certain hard drive errors.

9. Choice o The choice command is used within a script or batch program to provide a

list of choices and return the value of that choice to the program.

10. Cls o he cls command clears the screen of all previously entered commands

and other text.

11. Command

o The command command starts a new instance of the command.com command interpreter.

12. Copy

o The copy command does exactly that - it copies one or more files from

one location to another.

13. Ctty

o The ctty command is used to change the default input and output devices

for the system.

14. Date

o The date command is used to show or change the current date.

15. Dblspace

o The dblspace command is used to create or configure DoubleSpace drives.

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o DriveSpace, executed using the drvspace command, is an updated version of DoubleSpace.

16. Debug

o The debug command starts Debug, a command line application used to test and edit programs.

17. Defrag

o The defrag command is used to defragment a drive you specify. The

defrag command is the command line version of Microsoft's Disk

Defragmenter.

18. Del

o The del command is used to delete one or more files.

o The del command is the same as the erase command.

19. Deltree

o The deltree command is used to delete a directory and all the files and

subdirectories within it.

20. Dir

o The dir command is used to display a list of files and folders contained inside the folder that you are currently working in.

o The dir command also displays other important information like the hard drive's serial number, the total number of files listed, their combined size, the total amount of free space left on the drive, and more.

21. Diskcomp

o The diskcomp command is used to compare the contents of two floppy

disks.

22. Diskcopy

o The diskcopy command is used to copy the entire contents of one floppy

disk to another.

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23. Doskey

o The doskey command is used to edit command lines, create macros, and

recall previously entered commands.

24. Dosshell

o The dosshell command starts DOS Shell, a graphical file management tool for MS-DOS.

o The dosshell command was only available up to MS-DOS 6.0 but most MS-DOS 6.22 installations were upgrades from previous versions so the dosshell command is usually still available.

25. Drvspace

o The drvspace command is used to create or configure DriveSpace drives.

o DriveSpace is an updated version of DoubleSpace, executed using the dblspace command.

26. Echo

o The echo command is used to show messages, most commonly from

within script or batch files. The echo command can also be used to turn

the echoing feature on or off.

27. Edit

o The edit command starts MS-DOS Editor, a tool used to create and modify text files.

28. Edlin

o The edlin command starts the Edlin tool which is used to create and modify text files from the command line.

o Edlin was only available up to MS-DOS 5.0 so unless your version of MS-DOS 6.22 was upgraded from 5.0, you likely won't see the edlin command. Later versions of Windows again included the edlin command.

29. Emm386

o The emm386 command is used to give MS-DOS access to more than 640

KB of memory.

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30. Erase

o The erase command is used to delete one or more files.

o The erase command is the same as the del command.

31. Exit

o The exit command is used to end the command.com session that you're currently working in.

32. Expand

o The expand command is used to extract a single file or a group of files

from a compressed file.

33. Fasthelp

o The fasthelp command provides more detailed information on any of the

other MS-DOS commands.

34. Fastopen

o The fastopen command is used to add a program's hard drive location to a special list stored in memory, potentially improving the program's launch time by removing the need for MS-DOS to locate the application on the drive.

35. Fc

o The fc command is used to compare two individual or sets of files and

then show the differences between them.

36. Fdisk

o The fdisk command is used to create, manage, and delete hard drive

partitions.

37. Find

o The find command is used to search for a specified text string in one or

more files.

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38. For

o The for command is used to run a specified command for each file in a set

of files. The for command is most often used within a batch or script file.

39. Format

o The format command is used to format a drive in the file system that you

specify.More »

40. Goto

o The goto command is used in a batch or script file to direct the command

process to a labeled line in the script.

41. Graphics

o The graphics command is used to load a program that can print graphics.

42. Help

o The help command provides more detailed information on other DOS

commands.

43. If

o The if command is used to perform conditional functions in a batch file.

44. Interlnk

o The interlnk command is used to connect two computers via a serial or

parallel connection to share files and printers.

45. Intersvr

o The intersvr command is used to start the Interlnk server and to copy

Interlnk files from one computer to another.

46. Keyb

o The keyb command is used to configure a keyboard for a specific

language.

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47. Label

o The label command is used to manage the volume label of a disk.

48. Lh

o The lh command is the shorthand version of the loadhigh command.

49. Loadfix

o The loadfix command is used to load the specified program in the first 64K of memory and then runs the program.

50. Loadhigh

o The loadhigh command is used to load a program into high memory and is

usually used from within the autoexec.bat file.

51. Md

o The md command is the shorthand version of the mkdir command.

52. Mem

o The mem command shows information about used and free conventional, upper, reserved, and extended (XMS) memory.

53. Memmaker

o The memmaker command is used to start MemMaker, a memory

optimization tool.

54. Mkdir

o The mkdir command is used to create a new folder.

55. Mode

o The mode command is used to configure system devices, most often

COM and LPT ports.

56. 56. More

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o The more command is used to display the information contained in a text

file. The more command can also be used to paginate the results of any

other MS-DOS command.

57. Move

o The move command is used to move one or files from one folder to

another. The move command is also used to rename directories.

58. Msav

o The msav command starts Microsoft Antivirus.

59. Msbackup

o The msbackup command starts Microsoft Backup, a tool used to back up

and restore one or more files.

60. Mscdex

o The mscdex command is used to provide CD-ROM access to MS-DOS.

61. Msd

o The msd command starts Microsoft Diagnostics, a tool used to display

information about your computer.

62. Nlsfunc

o The nlsfunc command is used to load information specific to a particular

country or region.

63. Path

o The path command is used to display or set a specific path available to

executable files.

64. Pause

o The pause command is used within a batch or script file to pause the processing of the file.

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o When the pause command is used, a "Press any key to continue…" message is displayed.

65. Power

o The power command is used to reduce the power consumed by a

computer by monitoring software and hardware devices.

66. Print

o The print command is used to print a specified text file to a specified

printing device.

67. Prompt

o The prompt command is used to customize the appearance of the MS-

DOS prompt.

68. Qbasic

o The qbasic command starts QBasic, the MS-DOS based programming

environment for the BASIC programming language.

69. Rd

o The rd command is the shorthand version of the rmdir command.

70. Rem

o The rem command is used to record comments or remarks in a batch or

script file.

71. Ren

o The ren command is the shorthand version of the rename command.

72. Rename

o The rename command is used to change the name of the individual file

that you specify.

73. Replace

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o The replace command is used to replace one or more files with one or

more other files.

74. Restore

o The restore command is used to restore files that were backed up using the backup command.

o The backup command was only available up to MS-DOS 5.00 but the restore command was included by default with later versions of MS-DOS to provide a way to restore files that were backed up in previous versions of MS-DOS.

75. Rmdir

o The rmdir command is used to delete a directory.

76. Scandisk

o The scandisk command is used to start Microsoft ScanDisk, a disk repair

program.

77. Set

o The set command is used to display, enable, or disable environment variables in MS-DOS.

78. Setver

o The setver command is used to set the MS-DOS version number that MS-DOS reports to a program.

79. Share

o The share command is used to install file locking and file sharing functions

in MS-DOS.

80. Shift

o The shift command is used to change the position of replaceable

parameters in a batch or script file.

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81. Smartdrv

o The smartdrv command installs and configures SMARTDrive, a disk

caching utility for MS-DOS.

82. Sort

o The sort command is used to read data from a specified input, sort that

data, and return the results of that sort to the MS-DOS prompt, a file, or

another output device.

83. Subst

o The subst command is used to associate a local path with a drive letter. The subst command is a lot like the net use command available in Windows except a local path is used instead of a shared network path.

o The subst command replaced the assign command beginning with MS-DOS 6.0.

84. Sys

o The sys command is used to copy the MS-DOS system files and

command interpreter to a disk. The sys command is used most often to

create a simple bootable disk or hard drive.

85. Time

o The time command is used to show or change the current time.

86. Tree

o The tree command is used to graphically display the folder structure of a

specified drive or path.

87. Type

o The type command is used to display the information contained in a text

file.

88. Undelete

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o The undelete command is used to undo a deletion performed with the MS-

DOS delete command.

89. Unformat

o The unformat command is used to undo the formatting on a drive

performed by the MS-DOS format command.

90. Ver

o The ver command is used to display the current MS-DOS version number.

91. Verify

o The verify command is used to enable or disable the ability of MS-DOS to

verify that files are written correctly to a disk.

92. Vol

o The vol command shows the volume label and serial number of a

specified disk, assuming this information exists. More »

93. Vsafe

o The vsafe command is used to start Vsafe, a basic virus protection system

for MS-DOS.

94. Xcopy

o The xcopy command can copy one or more files or directory trees from

one location to another.

Basic DOS commands

Command and Usage Examples

ATTRIB Change file attributes. '+' adds an attribute, '-' removes it. Attributes are: A=archive; R=read

ATTRIB -R -A -S -H <VIRUS.EXE> All these attributes will be removed from virus.exe.

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only; S=system; H=hidden.

C: Go to the C: drive. Similarly A: and D: etc.

C:

CD Change directory. When you change directory, the prompt changes, showing the path of the directory you are currently in.

Note, directory is the term used by DOS for what Windows calls a folder.

CD\ takes you to the top of the directory tree (typically to C:) .

CD.. moves you one level up the directory tree (i.e. up towards the root directory).

CD <DIRECTORYNAME> takes you to that directory. You can use one or more subdirectory names, separated by \ e.g. CD WINNT\Media takes you to the directory C:\WINNT\Media

To change to another path, type the full path with slashes. e.g. CD \WINDOWS\SYSTEM

CLS Clear the screen.

CLS

DEL Delete one or more files in the current directory. Can be used with the '*' and the '?' wildcards.

DEL *.* will delete ALL files in the current directory, USE WITH CAUTION.

(Note: DEL cannot be used to delete directories. Use RD to remove a directory.)

DEL <VIRUS.EXE> deletes virus.exe

DEL *.JPG will delete all files with the extension JPG.

DEL MY*.* will delete all files beginning with MY and with any extension.

DEL MY??.* will delete files that are 4 characters long and begin with MY and with any extension.

DIR Displays the contents of a directory (folder).

Note, directory is the term used by DOS for what Windows calls a folder.

These switches can be combined, so DIR /W /P will return multiple rows listing a page at a

DIR displays all files and folders in the current directory. Folders are indicated in the list by <DIR>. Files are usually listed by name.

DIR /P displays the contents a page at a time, i.e. as many as will fit in your command line window. Press any key to

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time.

You can use the '*' and the '?' wildcards to search for a particular file. The ? character represents ONE character, and the * character represents multiple characters.

DIR *.* lists all the files in a directory.

display the next page.

DIR /W displays the files/folders in multiple rows. This view gives less information per file.

DIR *.JPG displays all files with the extension JPG in the current directory and all subdirectories.

DIR MY??.* displays all files beginning with MY, exactly 4 characters long, and with any extension.

DIR /S lists the contents of all subdirectories.

DIR /AH displays all hidden files.

EDIT Runs DOS EDIT (a simple text editor). Useful for editing batch files and viewing logs. This command requires QBASIC.EXE to be present.

EDIT <VIRUSLOG.TXT> opens the file viruslog.txt and allows you to edit it.

EDIT <NEWFILE.TXT> creates a new file called newfile.txt and opens it up for you to edit.

HELP Displays DOS Help. For help on an individual command, type HELP then the command for which you want more information.

HELP DIR displays information on the DIR command.

MD Make directory. Creates a new directory below the current one. (The command can also be written as MKDIR)

MD <NEWDIR> creates a new directory called Newdir.

PRINT Prints the specified file (if the printer is supported in DOS - many are not).

PRINT <LOGFILE.TXT>

Prints LOGFILE.TXT

RD Remove directory. Removes a subdirectory of the current directory. The directory you want to remove must be empty of all files. (The command can also be written as

RD <DIRECTORYNAME>

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RMDIR)

RENAME Rename a file. You must use the full file name including the suffix.

RENAME <OLDNAME.EXE> <NEWNAME.EXE>

TYPE Displays the contents of a file on the screen. If you use this command on a file which is not a text file, the display will be unintelligible. Use with "|MORE" to display the text on a page by page basis, and prevent it scrolling off the screen. "|" is a pipe character.

TYPE C:\README.TXT|MORE

> When you run a DOS command, output is usually sent to the screen. Use > to redirect output from the screen to a file. It runs the command preceding the >, creates a file in the current directory with the name you specify, and sends the information/output returned by the command, to that file.

COMMAND > FILENAME.TXT

e.g. SWEEP > REPORT.TXT The details of any infected files reported by SWEEP are sent to a file called REPORT.TXT.

How to Access Command Prompt?

Accessing the command prompt from Windows

To access the command prompt from Windows (a 'DOS box'), do as follows:

At the taskbar, select Start/Run. 1. Type

CMD or on some versions of Windows COMMAND

2. Click 'OK'. 3. A command prompt will open.

Accessing the command prompt in safe mode

For Windows NT/2000/XP/2003, see the knowledgebase article on removing files with SAV32CLI.

For Windows 95/98/Me you can boot from a start up disk, or use MS DOS mode 1. At the taskbar, select Start/Shut downs. 2. Select 'Restart in MS-DOS mode'. 3. Click 'OK'.

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What is Internal Command?

An internal command is an MS-DOS command

that is stored in the system memory and loaded

from the command.com. The illustration shows

how commands contained within command.com

are part of the command.com file. However, with

the external commands, each of the commands is

their own separate files.

Below are examples of internal commands in MS-

DOS and the Windows command line currently

listed in the Computer Hope database.

Assoc

Atmadm

Break

Call

CD

Chdir

Cls

Color

Copy

Ctty

Date

Del

Dir

Drivparm

Echo

Endlocal

Erase

Exit

For

Goto

If

LH

Loadhigh

Lock

Md

Mkdir

Mklink

Move

Path

Pause

Popd

Prompt

Pushd

Rd

Ren

Rename

Rmdir

Set

Setlocal

Shift

Start

Switches

Time

Title

Type

Unlock

Ver

Verify

Vol

82

Internal Commands

BREAK

CALL

CHCP

CHDIR(CD)

CLS

COPY

CTTY

DATE

DEL(ERASE)

DIR

ECHO

EXIT

FOR

GOTO

IF

MKDIR(MD)

PATH

PAUSE

PROMPT

REM

RENAME(REN)

RMDIR(RD)

SET

SHIFT

83

TIME

TYPE

VER

VERIFY

VOL

What is External Command?

An external command is an MS-DOS command

that is not included in command.com. External

commands are commonly external either

because they require large requirements or are

not commonly used commands. The illustration

shows each of the external commands are their

own separate files. However, the internal

commands are all included in the

command.com file.

Below are examples of MS-DOS and Windows

command line external commands currently listed on Computer Hope.

Append

Arp

Assign

At

Attrib

Backup

Bcdedit

Bootsect

Cacls

Chcp

Chkdsk

Chkntfs

Edit

Edlin

Expand

Extract

Fasthelp

Fc

Fdisk

Find

Forfiles

Format

FTP

Gpupdate

Mwbackup

Msd

Nbtstat

Net

Netsh

Netstat

Nlsfunc

Nslookup

Pathping

Ping

Power

Print

Systeminfo

Taskkill

Tasklist

Telnet

Tracert

Tree

Tskill

Undelete

Unformat

Wmic

Xcopy

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Choice

Cipher

Comp

Compact

Convert

Debug

Defrag

Delpart

Deltree

Diskcomp

Diskcopy

Doskey

Dosshell

Dumpchk

Graftabl

Help

Hostname

Ipconfig

Label

Loadfix

logoff

Mem

Mode

More

Msav

Msbackup

Mscdex

Mscdexnt

Reg

Robocopy

Route

Runas

Scandisk

Scanreg

Setver

Sfc

Share

Shutdown

Smartdrv

Sort

Subst

Sys

External Commands

APPEND.EXE

ASSIGN.COM

ATTRIB.EXE

BACKUP.EXE

CHKDSK.EXE

COMMAND.COM

COMP.EXE

DEBUG.EXE

DISKCOMP.COM

DISKCOPY.COM

DOSKEY.COM

DOSSHELL.COM

EDIT.COM

85

EDLIN.EXE

EMM386.EXE

EXE2BIN.EXE

EXPAND.EXE

FASTOPEN.EXE

FC.EXE

FDISK.EXE

FORMAT.COM

GRAFTABLE.COM

GRAPHICS.COM

HELP.EXE

JOIN.EXE

KEYB.COM

LABEL.EXE

MEM.EXE

MIRROR.COM

MODE.COM

MORE.COM

NLSFUNC.EXE

PRINT.EXE

QBASIC.EXE

RECOVER.EXE

REPLACE.EXE

RESTORE.EXE

SETVER.EXE

SHARE.EXE

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SORT.EXE

SUBST.EXE

SYS.COM

TREE.COM

UNDELETE.EXE

UNFORMAT.COM

XCOPY.EXE

WINDOWS

Microsoft Windows is a series of graphical interface operating systems developed,

marketed, and sold by Microsoft.

Microsoft introduced an operating environment named Windows on November 20, 1985

as a graphical operating system shell for MS-DOS in response to the growing interest

in graphical user interfaces (GUIs). Microsoft Windows came to dominate the

world's personal computer market with over 90% market share, overtaking Mac OS,

which had been introduced in 1984.

As of April 2014, the most recent versions of Windows for personal

computers, smartphones, server computers and embedded devices are

respectively Windows 8.1, Windows Phone 8.1, Windows Server 2012 R2 and Windows

Embedded 8.

Microsoft Windows

87

Screenshot of Windows 8.1, showing its Start

screen

Company / developer Microsoft

Written in Assembly, C, C++

OS family Windows 9x, Windows

CE and Windows NT

Working state Publicly released

Source model Closed / Shared source

Initial release November 20, 1985; 28

years ago, as Windows

1.0

Latest release 6.3.9600 (October 17,

2013; 9 months ago) [±]

Marketing target Personal computing

Available in 137 languages

Update method Windows Update Windows Anytime

Upgrade

88

Windows Store WSUS

Package manager Windows

Installer (.msi),Windows

Store (.appx)

Platforms ARM, IA-

32, Itanium, x86-64

Kernel type Windows NT family: Hybrid

Windows 9x and earlier: Monolithic (MS-DOS)

Default user interface Windows shell

License Proprietary commercial

software

Official website windows.microsoft.com

HISTORY OF WINDOWS

In 1983, Microsoft announced the development of Windows, a graphical user interface (GUI) for its own operating system (MS-DOS). The product line has changed from a GUI product to a modern operating system over two families of design, each with its own codebase and default file system.

The 3.x and 4.x family includes Windows 3.0, Windows 3.1x, Windows 95, Windows 98, and Windows ME. Windows for Workgroups 3.11 added 32-bit networking and 32-bit disk access. Windows 95 added additional 32-bit capabilities (however, MS-DOS, some of the kernel, and supplementary utilities such as Disk Defragment remained 16-bit) and implemented a new object oriented user interface, elements of which are still used today.

The Windows NT family started with Windows NT 3.1 in 1993. Modern Windows operating system versions are based on the newer Windows NT kernel that was originally intended for OS/2. Windows runs on IA-32, x86-64, and in Windows RT on 32-bit ARM (ARMv7) processors. Earlier versions also ran on the i860, Alpha, MIPS, Fairchild Clipper, PowerPC, and Itanium architectures. Some work was done to port it to the SPARC architecture.

The familiar Windows Explorer desktop shell superseded Program Manager with the release of Windows 95, received major enhancements in 1997, and remained the

89

default shell for all commercial Windows releases until Windows 8's Modern UI-derived Start screen debuted in 2012.

Remember: Bill Gates is one of the Founder of Microsoft Windows. His true name is William Henry Gates III. He is the wealthiest man in the world.

WINDOWS 1 AND WINDOWS 2

The history of Windows dates back to

September 1981, when Chase Bishop, a

computer scientist, designed the first model

of an electronic device and project

"Interface Manager" was started. It was

announced in November 1983 (after

the Apple Lisa, but before the Macintosh)

under the name "Windows", but Windows

1.0 was not released until November 1985. Windows 1.0 was to compete with Apple's

operating system, but achieved little popularity. Windows 1.0 is not a complete

operating system; rather, it extends MS-DOS. The shell of Windows 1.0 is a program

known as the MS-DOS Executive. Components

included Calculator, Calendar, Cardfile, Clipboard viewer, Clock, Control

Panel, Notepad, Paint, Reversi, Terminal and Write. Windows 1.0 does not allow

overlapping windows. Instead all windows are tiled. Only modal dialog boxes may

appear over other windows.

Windows 2.0 was released in December 1987 and was more popular than its

predecessor. It features several improvements to the user interface and memory

management. Windows 2.03 changed the OS from tiled windows to overlapping

windows. The result of this change led to Apple Computer filing a suit against Microsoft

alleging infringement on Apple's copyrights. Windows 2.0 also introduced more

sophisticated keyboard shortcuts and could make use of expanded memory.

Windows 2.1 was released in two different versions: Windows/286 and Windows/386.

Windows/386 uses the virtual 8086 mode of Intel 80386 to multitask several DOS

programs and the paged memory model to emulate expanded memory using

available extended memory. Windows/286, in spite of its name, runs on both Intel

8086 and Intel 80286processors. It runs in real mode but can make use of the high

memory area.

90

In addition to full Windows-packages, there were runtime-only versions that shipped

with early Windows software from third parties and made it possible to run their

Windows software on MS-DOS and without the full Windows feature set.

The early versions of Windows are often thought of as graphical shells, mostly because

they ran on top of MS-DOS and use it for file system services. However, even the

earliest Windows versions already assumed many typical operating system functions;

notably, having their own executable file format and providing their own device

drivers(timer, graphics, printer, mouse, keyboard and sound). Unlike MS-DOS,

Windows allowed users to execute multiple graphical applications at the same time,

through cooperative multitasking. Windows implemented an elaborate, segment-based,

software virtual memory scheme, which allows it to run applications larger than

available memory: code segments and resources are swapped in and thrown away

when memory became scarce; data segments moved in memory when a given

application had relinquished processor control.

Windows 3.0 and 3.1

Windows 3.0, released in 1990, improved the

design, mostly because of virtual memory and

loadable virtual device drivers (VxDs) that allow

Windows to share arbitrary devices between multi-

tasked DOS applications. Windows 3.0

applications can run in protected mode, which

gives them access to several megabytes of

memory without the obligation to participate in the

software virtual memory scheme. They run inside

the same address space, where the segmented memory provides a degree of

protection. Windows 3.0 also featured improvements to the user interface. Microsoft

rewrote critical operations from C into assembly. Windows 3.0 is the first Microsoft

Windows version to achieve broad commercial success, selling 2 million copies in the

first six months.

Windows 3.1, made generally available on March 1, 1992, featured a facelift. In August

1993, Windows for Workgroups, a special version with integrated peer-to-peer

networking features and a version number of 3.11, was released. It was sold along

Windows 3.1. Support for Windows 3.1 ended on December 31, 2001.

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Windows 9x

The next major consumer-oriented release of Windows, Windows 95, was released on

August 24, 1995. While still remaining MS-DOS-based, Windows 95 introduced support

for native 32-bit applications, plug and play hardware, preemptive multitasking, long file

names of up to 255 characters, and provided increased stability over its predecessors.

Windows 95 also introduced a redesigned, object oriented user interface, replacing the

previous Program Manager with the Start menu, taskbar, and Windows Explorer shell.

Windows 95 was a major commercial success for Microsoft; Ina Fried

of CNET remarked that "by the time Windows 95 was finally ushered off the market in

2001, it had become a fixture on computer desktops around the world." Microsoft

published four OEM Service Releases (OSR) of Windows 95, each of which was

roughly equivalent to a service pack. The first OSR of Windows 95 was also the first

version of Windows to be bundled with Microsoft's web browser, Internet

Explorer. Mainstream support for Windows 95 ended on December 31, 2000 and

extended support for Windows 95 ended on December 31, 2001.

Windows 95 was followed up with the release of Windows 98 on June 25, 1998, which

introduced the Windows Driver Model, support for USB composite devices, support

for ACPI, hibernation, and support for multi-monitor configurations. Windows 98 also

included integration with Internet Explorer 4 through Active Desktop and other aspects

of the Windows Desktop Update (a series of enhancements to the Explorer shell which

were also made available for Windows 95). In May 1999, Microsoft released Windows

98 Second Edition, an updated version of Windows 98. Windows 98 SE added Internet

Explorer 5.0 and Windows Media Player 6.2 amongst other upgrades. Mainstream

support for Windows 98 ended on June 30, 2002 and extended support for Windows 98

ended on July 11, 2006.

On September 14, 2000, Microsoft released Windows ME (Millennium Edition), the last

DOS-based version of Windows. Windows ME incorporated visual interface

enhancements from its Windows NT-based counterpart Windows 2000, had faster boot

times than previous versions (which however, required the removal of the ability to

access a real mode DOS environment, removing compatibility with some older

programs), expanded multimedia functionality (including Windows Media Player

7, Windows Movie Maker, and the Windows Image Acquisition framework for retrieving

images from scanners and digital cameras), additional system utilities such as System

File Protection and System Restore, and updated home networking tools. However,

Windows ME was faced with criticism for its speed and instability, along with hardware

compatibility issues and its removal of real mode DOS support. PC World considered

92

Windows ME to be one of the worst operating systems Microsoft had ever released, and

the 4th worst tech product of all time.

Windows NT

Early versions

In November 1988, a new development team within Microsoft (which included

former Digital Equipment Corporation developers Dave Cutler and Mark Lucovsky)

began work on a revamped version of IBM and Microsoft's OS/2 operating system

known as "NT OS/2". NT OS/2 was intended to be a secure, multi-user operating

system with POSIX compatibility and a modular, portable kernel with preemptive

multitasking and support for multiple processor architectures. However, following the

successful release of Windows 3.0, the NT development team decided to rework the

project to use an extended 32-bit port of the Windows API known as Win32 instead of

those of OS/2. Win32 maintained a similar structure to the Windows APIs (allowing

existing Windows applications to easily be ported to the platform), but also supported

the capabilities of the existing NT kernel. Following its approval by Microsoft's staff,

development continued on what was now Windows NT, the first 32-bit version of

Windows. However, IBM objected to the changes, and ultimately continued OS/2

development on its own.

The first release of the resulting operating system, Windows NT 3.1 (named to

associate it with Windows 3.1) was released in July 1993 with versions for

desktop workstations and servers. Windows NT 3.5 was released in September 1994,

focusing on performance improvements and support for Novell's NetWare, and was

followed up by Windows NT 3.51 in May 1995, which included additional improvements

and support for the PowerPC architecture. Windows NT 4.0 was released in June 1996,

introducing the redesigned interface of Windows 95 to the NT series. On February 17,

2000, Microsoft released Windows 2000, a successor to NT 4.0. The Windows NT

name was dropped at this point in order to put a greater focus on the Windows brand.

Windows XP

The next major version of Windows, Windows XP, was released on October 25, 2001.

The introduction of Windows XP aimed to unify the consumer-oriented Windows

9x series with the architecture introduced by Windows NT, a change which Microsoft

promised would provide better performance over its DOS-based predecessors.

Windows XP would also introduce a redesigned user interface (including an updated

Start menu and a "task-oriented" Windows Explorer), streamlined multimedia and

networking features, Internet Explorer 6, integration with Microsoft's .NET

93

Passport services, modes to help provide compatibility with software designed for

previous versions of Windows, and Remote Assistance functionality.

At retail, Windows XP was now marketed in two main editions: the "Home" edition was

targeted towards consumers, while the "Professional" edition was targeted towards

business environments and power users, and included additional security and

networking features. Home and Professional were later accompanied by the "Media

Center" edition (designed for home theater PCs, with an emphasis on support

for DVD playback, TV tuner cards, DVR functionality, and remote controls), and the

"Tablet PC" edition (designed for mobile devices meeting its specifications for a tablet

computer, with support for stylus pen input and additional pen-enabled applications).

Mainstream support for Windows XP ended on April 14, 2009. Extended support ended

on April 8, 2014.

After Windows 2000, Microsoft also changed its release schedules for server operating

systems; the server counterpart of Windows XP, Windows Server 2003, was released in

April 2003. It was followed in December 2005 by Windows Server 2003 R2.

Windows Vista and later

After a lengthy development process, Windows Vista was released on November 30,

2006 for volume licensing and January 30, 2007 for consumers. It contained a number

of new features, from a redesigned shell and user interface to significant technical

changes, with a particular focus on security features. It was available in a number

of different editions, and has been subject to some criticism. Vista's server

counterpart, Windows Server 2008 was released in early 2008.

On July 22, 2009, Windows 7 and Windows Server 2008 R2 were released as RTM

(release to manufacturing) while the former was released to the public 3 months later on

October 22, 2009. Unlike its predecessor, Windows Vista, which introduced a large

number of new features, Windows 7 was intended to be a more focused, incremental

upgrade to the Windows line, with the goal of being compatible with applications and

hardware with which Windows Vista was already compatible. Windows 7 has multi-

touch support, a redesigned Windows shell with an updated taskbar, a home networking

system called Home Group, and performance improvements.

Windows 8, the successor to Windows 7, was released generally on October 26, 2012.

A number of significant changes were made on Windows 8, including the introduction of

a user interface based around Microsoft's Metro design language with optimizations

for touch-based devices such as tablets and all-in-one PCs. These changes include

94

the Start screen, which uses large tiles that are more convenient for touch interactions

and allow for the display of continually updated information, and a new class

of apps which are designed primarily for use on touch-based devices. Other changes

include increased integration with cloud services and other online platforms (such

as social networks and Microsoft's own SkyDrive and Xbox Live services), the Windows

Store service for software distribution, and a new variant known as Windows RT for use

on devices that utilize the ARM architecture. An update to Windows 8, called Windows

8.1, was released on October 17, 2013, and includes features such as new live tile

sizes, deeper SkyDrive integration, and many other revisions.

There are three main issues involved in making English-language Windows multilingual:

(1) some languages require an Input Method Editor (IME) to enter text, (2) many users

want application menus (such as MS Office menus) to display in their own language,

and they may also want to use a keyboard that matches the normal keyboard layout

and marking for their own language, and (3) some users want Windows menus and

messages to display in their own language, i.e. they want to be able to switch from an

English Windows environment to another language.

For languages like Italian, Spanish, French and German, (2) alone may suffice. For

languages like Chinese, Japanese, and Korean (CJK), an IME (1) is also required. This

is bundled with the corresponding language version of Windows, but is also available as

a separate download for English Windows, as described below; (1) and (2) can be

essentially free (apart from the custom keyboard). For some languages, (3), multilingual

support for Windows, is a free download for Windows XP and later—but it requires

Windows 7 Ultimate or better for languages such as Chinese, Japanese, and Korean.

(1) After releasing Chinese, Japanese, and Korean bundles of Office 2010 and IME

2010, Microsoft made IME 2010 available as a free upgrade for users of the

earlier IMEversions of Windows. Microsoft later made these Chinese, Japanese, and

Korean IME versions available free to users of Windows XP and later, including English

Windows XP (but now says that users should own some version of MS Office). Each

IME package enables the entering of text in the corresponding language; necessary

fonts may be bundled with it (or supplementary fonts offered with the corresponding

version of Office).

(2) Microsoft now also offers Language Interface Packs (LIPs) for MS Office. Some LIPs

are free; some "Language Packs" (such as the CJK ones) are sold separately and may

include spelling and grammar checking tools. (Recent application software from some

companies may support two or more popular languages).

95

(3) Microsoft now also offers Language Interface Packs (LIPs) that allow users to view

Windows menus, dialog boxes, and other user interface items in their preferred

language. These are free; most are for English Windows (XP and later)—however,

Chinese, Japanese, and Korean LIP downloads require Windows 7 Ultimate or

Enterprise. These LIPs include IMEs where applicable.

Platform support

Windows NT included support for several different platforms before the x86-

based personal computer became dominant in the professional world. Windows NT

4.0 and its predecessors supported PowerPC, DEC Alpha and MIPS R4000. (Although

some these platforms implement 64-bit computing, the operating system treated them

as 32-bit.) However, Windows 2000, the successor of Windows NT 4.0, dropped

support for all platforms except the third generation x86 (known as IA-32) or newer in

32-bit mode. The client line of Window NT family still runs on IA-32, although

the Windows Server line has ceased supporting this platform with the release

of Windows Server 2008 R2.

With the introduction of the Intel Itanium architecture (IA-64), Microsoft released new

versions of Windows to support it. Itanium versions of Windows XP and Windows

Server 2003were released at the same time as their mainstream x86 counterparts.

Windows XP 64-Bit Edition, released in 2005, is the last Windows client operating

systems to support Itanium. Windows Server line continued to support this platform

until Windows Server 2012; Windows Server 2008 R2 is the last Windows operating

system to support Itanium architecture.

On April 25, 2005, Microsoft released Windows XP Professional x64 Edition and

Windows Server 2003 x64 Editions to support the x86-64 (or simply x64), the eighth

generation of x86 architecture. Windows Vista was the first client version of Windows

NT to be released simultaneously in IA-32 and x64 editions. x64 is still supported.

An edition of Windows 8 known as Windows RT was specifically created for computers

with ARM architecture.

Windows CE

The latest current version of Windows CE,

Windows Embedded Compact 7, displaying a

concept media player UI.

Windows CE (officially known as Windows

Embedded Compact), is an edition of Windows that

96

runs on minimalistic computers, like satellite navigation systems and some mobile

phones. Windows Embedded Compact is based on its own dedicated kernel, dubbed

Windows CE kernel. Microsoft licenses Windows CE to OEMs and device makers. The

OEMs and device makers can modify and create their own user interfaces and

experiences, while Windows CE provides the technical foundation to do so.

Windows CE was used in the Dreamcast along with Sega's own proprietary OS for the

console. Windows CE was the core from which Windows Mobile was derived. Its

successor, Windows Phone 7, was based on components from both Windows CE 6.0

R3 and Windows CE 7.0. Windows Phone 8 however, is based on the same NT-kernel

as Windows 8.

Windows Embedded Compact is not to be confused with Windows XP

Embedded or Windows NT 4.0 Embedded, modular editions of Windows based on

Windows NT kernel.

Windows 7 and Windows Server 2008 R2

Windows 7 was released to manufacturing on 22 July

2009, and reached general retail availability on 22

October 2009. It was previously known by the

codenames Blackcomb and Vienna. Windows 7 has

the version number NT 6.1.

Some features of Windows 7 are faster booting, Device

Stage, Windows PowerShell, less obtrusive User

Account Control, multi-touch, and improved window management. Features included

with Windows Vista and not in Windows 7 include the sidebar (although gadgets

remain) and several programs that were removed in favor of downloading

their Windows Live counterparts.

Windows 7 ships in six editions:

Starter (available worldwide)

Home Basic

Home Premium

Professional

Enterprise (available to volume-license business customers only)

Ultimate (available to retail market with limited availability to OEMs)

97

In some countries (Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic,

Denmark, Estonia, Finland, France, Germany, United Kingdom, Greece, Hungary,

Iceland, Ireland, Italy, Latvia, Liechtenstein, Lithuania, Luxembourg, Malta, Netherlands,

Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, and

Switzerland), there are other editions that lack some features such as Windows Media

Player, Windows Media Center and Internet Explorer called names such as "Windows 7

N." Microsoft focuses on selling Windows 7 Home Premium and Professional. All

editions, except the Starter edition, are available in both 32-bit and 64-bit versions.

Unlike the corresponding Vista editions, the Professional and Enterprise editions are

supersets of the Home Premium edition.

At the Professional Developers Conference (PDC) 2008, Microsoft also

announced Windows Server 2008 R2, as the server variant of Windows 7. Windows

Server 2008 R2 ships in 64-bit versions (x64 and Itanium) only.

Windows Home Server 2011

Windows Home Server 2011 code named 'Vail' was released on 6 April 2011. Windows

Home Server 2011 is built on the Windows Server 2008 R2 code base. It follows the

release of Windows Home Server Power Pack 3 which added support for Windows 7 to

Windows Home Server. Windows Home Server 2011 is considered a "major release".

(Its predecessor having been built on Windows Server 2003) and only supports x86-

64 hardware.

Windows Thin PC

In 2011, Microsoft introduced Windows Thin PC or WinTPC, which is a feature- and

size-reduced locked-down version of Windows 7 expressly designed to turn older PCs

into thin clients. WinTPC is available for software assurance customers and relies

on cloud computing in a business network. Wireless operation is supported since

WinTPC has full wireless stack integration, but wireless operation may not be as good

as the operation on a wired connection.

Windows 8 and Windows Server 2012

Main articles: Windows 8, Windows Server

2012, Windows 8.1 and Windows Server 2012 R2

Windows 8 is the current version of Microsoft

Windows. One edition, Windows RT, runs on some

system-on-a-chip devices with mobile 32-bit ARM

(ARMv7) processors. Windows 8 features a

98

redesigned user interface, designed to make it easier for touchscreen users to use

Windows. The interface introduced an updated Start menu known as the Start screen,

and a new full-screen application platform. The desktop interface is also present for

running windowed applications, although Windows RT will not run any desktop

applications not included in the system. On the Building Windows 8 blog, it was

announced that a computer running Windows 8 can boot up much faster than Windows

7. New features also include USB 3.0 support, the Windows Store, the ability to run

from USB drives with Windows To Go, and others. Windows 8 has the version number

NT 6.2

Windows 8 is available in the following editions:

Windows 8

Windows 8 Pro

Windows 8 Enterprise

Windows RT

The first public preview of Windows Server 2012 was also shown by Microsoft at the

2011 Microsoft Worldwide Partner Conference.

Windows 8 Release Preview and Windows Server 2012 Release Candidate were both

released on 31 May 2012. Product development on Windows 8 was completed on 1

August 2012, and it was released to manufacturing the same day. Windows Server

2012 went on sale to the public on 4 September 2012. Windows 8 went on sale 26

October 2012.

Windows 8.1 and Windows Server 2012 R2 were released on 17 October 2013.

Windows 8.1 has the version number NT 6.3. Windows 8.1 is available as an update in

the Windows store only for Windows 8 users and also available to download for clean

installation. The update adds new options for resizing the live tiles on the Start screen.

Product Progression

Original Line

Windows 1.0

Windows 2.0

Windows 2.1 (Windows/286 and Windows/386)

Windows 3.0

Windows 3.1 (with a respective Windows for Workgroups release)

Windows 3.11 (also with a respective Windows for Workgroups release)

Windows 3.2 (a minor update to 3.1 for Simplified Chinese support)

99

Windows 9x

Windows 95 (version 4.0)

Windows 98 and Windows 98 SE (version 4.1)

Windows ME (version 4.9)

Windows NT

Windows NT 3.1

Windows NT 3.5

Windows NT 3.51

Windows NT 4.0

Windows 2000 (NT version 5.0)

Windows XP and Windows Fundamentals for Legacy PCs (NT version 5.1)

Windows Server 2003 and Windows XP Professional x64 Edition (NT version

5.2)

Windows Vista and Windows Server 2008 (NT version 6.0)

Windows 7 and Windows Server 2008 R2 (NT version 6.1)

Windows 8, Windows RT and Windows Server 2012 (NT version 6.2)

Windows 8.1, Windows RT 8.1, and Windows Server 2012 R2 (NT version 6.3)

Windows 9 (NT version 6.4)

Timeline of releases

The Windows family tree

100

LINUX/UNIX

It is a Unix-like and mostly POSIX-

compliant computer operating

system assembled under the model

of free and open source

software development and distribution.

The defining component of Linux is

the Linux kernel, an operating system

kernel first released on 5 October

1991 by Linus Torvalds. The Free

Software Foundation uses the

name GNU/Linux, which has led to some controversy.

Linux was originally developed as a free operating system for Intel x86-based personal

computers. It has since been ported to more computer hardware platforms than any

other operating system. It is a leading operating system on servers and other big

iron systems such as mainframe computers and supercomputers. As of June 2013,

more than 95% of the world's 500 fastest supercomputers run some variant of

Linux, including all the 44 fastest. Linux also runs on embedded systems, which are

devices whose operating system is typically built into the firmware and is highly tailored

to the system; this includes mobile phones, tablet computers, network routers, facility

automation controls, televisions and video game consoles. Android, which is a widely

used operating system for mobile devices, is built on top of the Linux kernel.

The development of Linux is one of the most prominent examples of free and open

source software collaboration. The underlying source code may be used, modified, and

distributed—commercially or non-commercially—by anyone under licenses such as the

GNU General Public License. Typically, Linux is packaged in a format known as a Linux

distribution for desktop and server use. Some popular mainstream Linux distributions

include Debian, Ubuntu, Linux Mint, Fedora, open SUSE, Arch Linux, and the

commercial Red Hat Enterprise Linux and SUSE Linux Enterprise Server. Linux

distributions include the Linux kernel, supporting utilities and libraries and usually a

large amount of application software to fulfill the distribution's intended use.

A distribution oriented toward desktop use will typically include X11, Wayland or Mir as

the windowing system, and an accompanying desktop environment such as GNOME or

the KDE Software Compilation. Some such distributions may include a less resource

101

intensive desktop such as LXDE or Xfce, for use on older or less powerful computers. A

distribution intended to run as a server may omit all graphical environments from the

standard install, and instead include other software to set up and operate a solution

stack such as LAMP. Because Linux is freely redistributable, anyone may create a

distribution for any intended use.

Linux

Tux the penguin, mascot of Linux

Company / dev

eloper

Community

Written in Various (Notably C and Assembly)

OS family Unix-like

Working state Current

Source model Mainly Free and open source software,

Proprietary software also available

Initial release 1991; 23 years ago

102

Latest release 3.16.1 (14 August 2014; 6 days ago) [±]

Marketing

target

Personal computers, mobile devices, embedded devices, servers,

mainframes, supercomputers

Available in Multilingual

Platforms Alpha, ARC, ARM,AVR32, Black fin, C6x,ETRAX CRIS, FR-

V,H8/300, Hexagon,Itanium, M32R, m68k,META, Microblaze,MIPS,

MN103,OpenRISC, PA-

RISC,PowerPC, s390,S+core, SuperH,SPARC, TILE64,Unicore32,

x86, Xtensa

Kernel type Monolithic (Linux kernel)

User land Various

Default user

interface

Many

License Many ("Linux" trademark owned by Linus Torvalds and administered

by the Linux Mark Institute)

UNIX

Unix (all-caps UNIX for the trademark) is

a multitasking, multiuser computer operating

system that exists in many variants. The

original Unix was developed at AT&T's Bell

Labs research center by Ken

Thompson, Dennis Ritchie, and others. From

the power user's or programmer's

perspective, Unix systems are characterized

by a modular design that is sometimes called

the "Unix philosophy," meaning the OS

103

provides a set of simple tools that each perform a limited, well-defined function, with a

unified file system as the main means of communication[1] and a shell scripting and

command language to combine the tools to perform complex workflows.

The C programming language was designed by Dennis Ritchie as a systems

programming language for Unix, allowing for portability beyond the initial PDP-

11 development platform and the use of Unix on numerous computing platforms.

While initially intended for use inside the Bell System, Unix developed into a standard

operating system for academia during the late 1970s and 1980s. AT&T tried to

commercialize it by licensing the OS to third-party vendors, leading to a variety of both

academic (e.g., BSD) and commercial variants of Unix (such as Xenix) and eventually

to the "Unix wars" between groups of vendors. AT&T finally sold its rights in Unix

to Novell in the early 1990s, which then sold its Unix business to the Santa Cruz

Operation (SCO) in 1995, but the UNIX trademark passed to the industry standards

consortium The Open Group, which allows the use of the mark for certified operating

systems compliant with the Single UNIX Specification.

Other operating systems that emulate Unix to some extent are often called Unix-like,

although the Open Group disapproves of this term. The term Unix is also often used

informally to denote any operating system that closely resembles the trademarked

system. The most common version of Unix (bearing certification) is Apple's OS

X, while Linux is the most popular non-certified work a like.

Unix

Evolution of Unix and Unix-like systems

Company / developer Ken Thompson,Dennis

104

Ritchie, Brian

Kernighan, Douglas

McIlroy, and Joe

Ossanna at Bell Labs

Written in C and Assembly

language

OS family Unix

Working state Current

Source model Historically closed

source, now some Unix

projects (BSD family

and Illumos) are open

sourced.

Initial release 1973; 41 years

ago[dubious – discuss]

Available in English

Kernel type Monolithic

Default user interface Command-line

interface & Graphical (X

Window System)

License Varies; some versions

are proprietary, others

are free/open source

software

105

Official website unix.org

HISTORY OFLINUX/UNIX

Simplified history of Unix-like operating systems. Linux shares similar architecture and

concepts (as part of the POSIX standard) but does not share non-free source code with

the original Unix or MINIX.

The primary difference between Linux and many other popular contemporary operating

systems is that the Linux kernel and other components are free and open source

software. Linux is not the only such operating system, although it is by far the most

widely used.Some free and open source software licenses are based on the principle

of copyleft, a kind of reciprocity: any work derived from a copyleft piece of software must

also be copyleft itself. The most common free software license, the GNU General Public

License (GPL), is a form of copyleft, and is used for the Linux kernel and many of the

components from the GNU Project.

Linux based distributions are intended by developers for interoperability with other

operating systems and established computing standards. Linux systems adhere

to POSIX, SUS,LSB, ISO, and ANSI standards where possible, although to date only

one Linux distribution has been POSIX.1 certified, Linux-FT.

Free software projects, although developed in a collaborative fashion, are often

produced independently of each other. The fact that the software licenses explicitly

permit redistribution, however, provides a basis for larger scale projects that collect the

software produced by stand-alone projects and make it available all at once in the form

of a Linux distribution.

Many Linux distributions, or "distros", manage a remote collection of system software

and application software packages available for download and installation through a

network connection. This allows users to adapt the operating system to their specific

needs. Distributions are maintained by individuals, loose-knit teams, volunteer

organizations, and commercial entities. A distribution is responsible for the default

configuration of the installed Linux kernel, general system security, and more generally

integration of the different software packages into a coherent whole. Distributions

typically use a package manager such as dpkg, Synaptic, YAST, yum, or Portage to

install, remove and update all of a system's software from one central location.

106

The History of Linux began in 1991 with the commencement of a personal project by

a Finnish student, Linus Torvalds, to create a new free operating system kernel.

Since then, the resulting Linux kernel has been marked by constant growth throughout

its history. Since the initial release of its source code in 1991, it has grown from a small

number of C files under a license prohibiting commercial distribution to the 3.10 version

in 2013 with more than 16 million lines of source code under the GNU General Public

License.

The history of Unix dates back to the mid-1960s when the Massachusetts Institute of

Technology, AT&T Bell Labs, and General Electric were developing an

experimental time sharing operating system called Multics for the GE-

645 mainframe. Multics introduced many innovations, but had many problems.

Bell Labs, frustrated by the size and complexity of Multics but not the aims, slowly

pulled out of the project. Their last researchers to leave Multics, Ken Thompson, Dennis

Ritchie, Doug McIlroy, and Joe Ossanna, decided to redo the work on a much smaller

scale. In 1979, Dennis Ritchie described their vision for Unix:

What we wanted to preserve was not just a good environment in which to

do programming, but a system around which a fellowship could form. We knew from

experience that the essence of communal computing, as supplied by remote-access,

time-shared machines, is not just to type programs into a terminal instead of

a keypunch, but to encourage close communication.

While Ken Thompson still had access to the Multics environment, he wrote simulations

for the new file and paging system on it. He also programmed a game called Space

Travel, but the game needed a more efficient and less expensive machine to run on,

and eventually he found a little-used PDP-7 at Bell Labs. On this PDP-7, in 1969, a

team of Bell Labs researchers led by Thompson and Ritchie, including Rudd Canaday,

developed a hierarchical file system, the concepts of computer processes and device

files, a command-line interpreter, and some small utility programs.

107

Summary:

Software - Software is a program that enables a computer to perform a specific task, as opposed to the physical components of the system (hardware).

DOS - Disk Operating System - refer to an operating system software used in most computers that provides the abstraction and management of secondary storage devices and the information on them (e.g., file systems for organizing files of all sorts)

2 TYPES DOS COMMAND

INTERNAL COMMAND - stored in the system memory and loaded from the command.com. EXAMPLE: cd, copy, date and time (common), dir, md, cls, del, etc.

EXTERNAL COMMAND - command that is not included in command.com. EXAMPLE: *.com, *.exe, *.bat, etc.

Windows - it is under Microsoft. It is a user friendly operating system. Bill Gates - one of the founders of Microsoft. William Henry Gates III his true name.

LINUX/UNIX - is a shareware operating system.

Chapter Quiz:

1. What is System Software?

2. What is Application Software?

3. What is Disk Operating System?

4. - 7. Give example of Internal Command.

8. - 10. Give example of External Command.

***Good Luck!***

108

THE BASIC COMPUTER COMPONENTS AND PERIPHERAL

What is it?

- It is refer o the basic part or component of a computer. - Peripheral devices can fit into one of four categories: input, output, storage or

networking devices. Examples of some common peripherals include: o Input devices - trackball, joystick, scanner, digital camera, digitizer,

barcode reader, microphone o Output devices - printer, plotter, speakers, headphones o Storage devices - secondary hard drive, external CD/DVD devices, flash

drives o Networking - external modems, external NIC

List of Computer Parts and Peripherals

Blank Media & Mass Storage

This refers to CD and DVD disc. CD, a compact disc is a flat round storage medium that is read by a laser in a CD-ROM drive. The standard CD is capable of holding 72 minutes of music or 650 MB of data. 80 minute CDs are also commonly used to store data and are capable of containing 700 MB of data.

Digital Versatile Disc or Digital Video Disc, DVD or DVD-ROM

It is a type of disc drive that allows for large amounts of data on one disc, the same size of a standard Compact Disc.

Batteries

It is a hardware device that supplies power to a device or appliance and enables that device or appliance to work without a power cord.

Computer Cases/Chassis

This is the housing that helps protect and organize all the components that make up your computer.

CD/DVD ROM Drives

CD-ROM drives are CD-Players inside computers that has the capability of playing audio CDs and computer data CDs. DVD-RW Drive is a technology that enables a user to read and write to a DVD+RW or DVD+R disc several times.

Hard drive

109

Computer's main storage media device, also called a hard disk drive or abbreviated as HD or HDD.

Memory/RAM

It is a term commonly used to describe the memory within a computer.

Memory Stick

Also known as a USB flash drive, is a portable memory disk, a small device (about the size of your index finger) that connects to a computer's USB port and often is capable of storing 512MB, 1GB, or more.

Mice and Keyboards o Keyboard

It is one of the main input devices used on a computer, a PC's keyboard looks very similar to the keyboards of electric typewriters, with some additional keys.

o Mouse

It is an input device that allows an individual to control a mouse pointer in a graphical user interface (GUI). Utilizing a mouse a user has the ability to perform various functions such as opening a program or file and does not require the user to memorize commands, like those used in a text-based environment such as MS-DOS.

Modems

It is a hardware device that enables a computer to transmit and receive information over telephone lines.

Monitor & Display

It is a video display screen and the hard shell that holds it. Is use to view or watch over someone or something.

Motherboard

It is a printed circuit that is the foundation of a computer and allows the CPU, RAM, and all other computer hardware components to function with each other.

Network Card

Network Interface Card, a NIC, also referred to as a "network adapter", is a printed circuit board containing the necessary hardware used to connect a computer to a network or other computer.

Power Supply

110

The PS is an internal hardware component used to supply the components within the computer with power. Besides properly supplying power to the computer and all its internal components, the power supply also converts the AC electrical current found in most standard wall sockets throughout the United States into a lower DC voltage that the computer components use.

Processor/CPU

It was first developed by Intel in 1974 Unit. The computer CPU is responsible for handling all instructions and calculation it receives from other hardware components in the computer and software programs running on the computer.

Printers

It is an external hardware device responsible for taking computer data and generating a hard copy of that data. Printers are one of the most used peripherals on computers and are commonly used to print text, images, and/or photos.

Scanners

Hardware input device that allows a user to take an image and/or text and convert it into a digital file, allowing the computer to read and/or display the scanned object. A scanner is commonly connected to a computer USB, Firewire, Parallel or SCSI port.

Sound Cards

Also known as a sound board or an audio card, a sound card is an expansion card or integrated circuit that provides a computer with the ability to produce sound that can be heard by the user.

Speakers

A hardware device connected to a computer's sound card that outputs sounds generated by the card.

TV Tuners

A TV tuner card is a computer component that allows television signals to be received by computer. Most TV tuners also function as video capture cards, allowing them to record television programs onto a hard disk.

UPS (Uninterruptible Power Supply)

Uninterruptible Power Supply, UPS is a hardware device that provides a backup power source in case of a power outage (blackout), brownout, or a surge in power. A UPS provides enough power for the computer or computers to shut down properly or to remain up during a temporary power outage.

Video/Graphic Cards

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Also known as a graphics card, video card, video board, or a video controller, a video adapter is an internal circuit board that allows a display device, such as a monitor, to display images from the computer.

Video Projectors

It is a hardware device that enables an image, such as a computer screen, to be projected onto a flat surface. These devices are commonly used in meetings and presentations as they allow for a large image to be shown so everyone in a room can see.

Webcams

A camera connected to a computer or server that allows anyone connected to the Internet to view still pictures or motion video of a user.

MONITOR (Computer Monitor)

A monitor displays information in visual form, using text and graphics. The portion of the

monitor that displays the information is called the screen. Like a television screen, a

computer screen can show still or moving pictures.

TYPES OF MONITOR

There are 5 types of Monitor. But we only know the 3 common type of it, the CRT

(Cathode Ray Tube), LCD (Liquid Crystal Display) and LED (Light Emitting Diode).

1. CRT o CRT (Cathode Ray Tube) computer monitors were the most common

computer monitors until flat panel screens became affordable. Similar to older TVs, CRT monitors still typically have much better contrast ratios and viewing angles than other computer monitor alternatives.

2. LCD o LCD (Liquid Crystal Display) computer monitors save a lot of space and

can even be mounted on walls. They provide a wide viewing angle and come in sizes typically ranging from 17-inches to 60-inches.

3. Plasma o Plasma computer monitors are less commonly used with computers due

to their high operating temperatures, high power consumption, and fixed resolution.

4. Touchscreen o Touchscreen computer monitors provide a new way of interacting with

your computer with a touch-sensitive screen. This allows users to interact directly with the application on screen without need for a mouse or keyboard.

112

5. OLED o OLED (Organic Light Emitting Display) computer monitors are much

thinner and brighter than LCD or Plasma screens. OLED monitors can also be placed on transparent surfaces, such as glass, allowing the user to see through them when not active.

Basic Part of Monitor

This is the illustration of Basic Parts of Monitor

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This is the Major Parts of Typical SVGA Monitor with Cover Removed.

CPU (Central Processing Unit)

It manipulates raw data into more useful form and controls the other parts of the

computer system.

Central Processing Unit (CPU), principal part of any digital computer system, generally

composed of the main memory, control unit, and arithmetic-logic unit. It constitutes the

physical heart of the entire computer system; to it is linked various peripheral

equipment, including input/output devices and auxiliary storage units (see input/output

device; computer memory).

The control unit of the central processing unit regulates and integrates the operations of

the computer. It selects and retrieves instructions from the main memory in proper

114

sequence and interprets them so as to activate the other functional elements of the

system at the appropriate moment to perform their respective operations. All input data

are transferred via the main memory to the arithmetic-logic unit for processing, which

involves the four basic arithmetic functions (i.e., addition, subtraction, multiplication, and

division) and certain logic operations such as the comparing of data and the selection of

the desired problem-solving procedure or a viable alternative based on predetermined

decision criteria.

Vital Parts of the Computer CPU

Function

o The central processing unit is called the CPU, processor or microprocessor. Modern processors are engineered on just one computer chip. The CPU is the device that receives various types of input and produces specific outputs. The majority of processors are capable of carrying out a single instruction at a time. However, the one instruction is executed at lighting speed. In fact, most personal computers have the capacity to perform directives in less than one-millionth of a second. Powerful supercomputers can execute commands in less than one-billionth of a second.

Control Unit

o The various parts of the computer's CPU are directed by the control unit. The control unit can be described as the manager of the CPU. It is comprised of electronic circuits that utilize electrical pulses to transmit signals to other components of the computer. The control unit instructs them to perform, or keep application commands. Its sole purpose is to guide other mechanisms in the system to complete specific tasks. The CU talks with the ALU and memory.

ALU

o The arithmetic logic unit (ALU) is one of the most important parts of the computer's CPU. It's comprised of electronic circuits that make it capable of executing arithmetic and logic operations. It works with different registers to store data or hold information about the latest action performed by the logic unit. The ALU has the ability to perform four types of arithmetic operations: addition, subtraction multiplication and division.

o The ALU also has the means to perform three kinds of logic comparisons: equal-to, less-than and greater-than. The ALU is capable of comparing letters, numbers or special characters. The personal computer then takes

115

action based on the results of the comparison. An example of such a comparison would be the following "less-than" operation: If the average test score of a student is less than 70 percent, then the student receives a "fail" grade; otherwise, the grade is "pass."

Registers

o Registers are temporary memory devices that are indispensable parts of the computer CPU. They are managed by the control unit. Registers are used as storage areas that contain data and other information that are often needed while a program is running. They are meant to be to be accessed very quickly. There are different types of registers, including instruction registers and test registers. The instruction register contains the instruction the CPU is currently executing. The test register is used to hold the results of calculations performed by the CPU.

Clock

o Another component that is included in parts of the computer CPU is the clock. The clock is made of timing circuitry that measures the timing of tasks performed by the CPU in terms of clock cycles. The performance of processors is generally measured by the clock rate or clock speed of the CPU. In theory, a higher clock speed means that the CPU can execute instructions (cycles) faster. The clock speed is measured in "hertz." Hertz refers to the quantity of clock cycles per second. A CPU with a speed of 1 GHz would mean that it performs one billion clock cycles per second.

MOTHERBOARD

What is Motherboard?

A motherboard (sometimes alternatively known as the mainboard, system board, planar board or logic board, or colloquially, a mobo) is the main printed circuit board (PCB) found in computers and other expandable systems. It holds many of the crucial electronic components of the system, such as the central processing unit (CPU) and memory, and provides connectors for other peripherals. Unlike a backplane, a motherboard contains significant sub-systems such as the processor and other components.

Motherboard specifically refers to a PCB with expansion capability and as the name suggests, this board is the "mother" of all components attached to it, which often include sound cards, video cards, network cards, hard drives, or other forms of persistent storage; TV tuner cards, cards providing extra USB or FireWire slots and a variety of other custom components (the term mainboard is applied to devices with a single board and no additional expansions or capability, such as controlling boards in televisions, washing machines and other embedded systems).

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Types of Motherboards

Motherboard is the most important component of a system. It is a Printed Circuit Board

(PCB) where all the components of a system are connected. The Central Processing

Unit (CPU), hard drives, memory and every other part of a system is connected to the

motherboard by means of slots, connectors and sockets. The motherboard chipset is a

series of chips that are a part of the motherboard. Types of Motherboards and the

capacity and efficiency of motherboards differ according to the type of system you use.

Motherboards are classified as integrated and Non-integrated devices depending on the

devices they support. Motherboards which have all the ports for connecting various

devices on board are known as integrated motherboards. All the latest desktop, server

and laptop boards are of the integrated type. Motherboards which do not support

connecting devices are known as Non-Integrated motherboards. Older boards were of

non integrated types.

Classification of Motherboards:

Integrated Motherboards

Integrated motherboards have all the peripheral device slots, input output ports, serial

and parallel ports are mounted on the board. The connectors for the various devices

such as the hard drive connector and floppy disk drive connector are installed directly

on to the motherboard. This arrangement saves a lot of space inside the system.

Integrated boards are cheaper in cost as compared to non-integrated motherboards.

The major disadvantage of these types of motherboards are that if an individual

component of the motherboard fails, the whole board may need to be replaced and that

can be a costly affair at times.

Non-integrated Motherboards

Non-Integrated motherboards have RAM slots integrated on the board. All the input-

output ports for devices such as the serial and parallel port connectors, other controllers

such as connectors for hard drive and floppy disk drives are attached to the system

using expansion boards. Expansion boards use more space of the cabinet. If any one of

the expansion boards fate, only those particular expansions board needs to be replaced

and not the whole board. This type of board is more costly as compared to integrated

board as all the devices and ports, and other connectors for the devices need to be

installed individually.

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The Non-integrated Motherboards are almost extinct because these types of

motherboards are costly and not very space efficient. Desktop Motherboards Desktop

Motherboards is used in personal computers and desktops. As it is used for applications

at home and in office, this type of motherboard is the most basic type.

Motherboard Compatibility

The NVIDIA Quadro® FX 4500 X2 architecture allows two graphics processing units

(GPUs) to be employed on a single graphics board for the industry’s most advanced

graphics. The following motherboards have been tested and passed NVIDIA's

compatibility testing requirements with the NVIDIA Quadro FX 4500 X2 graphics board*.

Compatible Professional Motherboards

Manufacturer Model Chipset System BIOS

iWill DK8EW 59102 NVIDIA nForce4 Pro 2200 V130

Tyan S2895 D/T NVIDIA nForce 2200/2050 2895_103k

ABIT AA8-DuraMAX Intel 925X 2.4

ABIT AW8 Intel 955X 1.4

ASUS P5WD2 Intel 955X 501

Intel D955XBK Intel 955X 2036

Intel D975XBX Intel 975X 1073

Intel SE7525GP2 Intel E7525 P08

Supermicro X6DA8 Intel E7525 1.0B

ABIT AB9 Pro Intel 965P 11

118

Full List of Compatible Motherboards

Manufacturer Model Chipset System BIOS

ABIT AA8-DuraMAX Intel 925X 2.4

ABIT AB9 Pro Intel 965P 11

ABIT AW8 Intel 955X 1.4

ABIT AN8 32X NVIDIA nForce4 SLI

X16 11

ABIT AN8 SLI NVIDIA nForce4 SLI 1.9

ABIT KN8 SLI NVIDIA nForce4 SLI 17

ABIT KN9 SLI NVIDIA nForce 570

SLI 10

Albatron K8SLI NVIDIA nForce4 SLI R1.12

ASUS

A8N32-SLI

Deluxe

NVIDIA nForce4 SLI

X16 1205

ASUS A8N5X NVIDIA nForce4 0902

ASUS A8N-E NVIDIA nForce4

Ultra 1013

ASUS A8N-SLI Deluxe NVIDIA nForce4 SLI 1016

ASUS

A8N-SLI

Premium NVIDIA nForce4 SLI 1011.006

ASUS

A8R32-MVP

Deluxe

ATI CrossFire Xpress

3200 0404

119

ASUS A8V-E Deluxe VIA

K8T890/VT8237R 1005

ASUS

M2N32-SLI

DELUXE

NVIDIA nForce 590

SLI 0404

ASUS

M2N32-WS

Professional

NVIDIA nForce 590

SLI WS 0112

ASUS

M2N-SLI

DELUXE

NVIDIA nForce 570

SLI 112

ASUS P5LD2 Intel 945P 1103

ASUS P5LD2-VM Intel 945G 0508

ASUS P5ND2-SLI NVIDIA nForce4 SLI 0304

ASUS

P5N32-SLI SE

Deluxe

NVIDIA nForce4 SLI

X16 0121

ASUS P5WD2 Intel 955X 0501

Biostar i945 G-M7 Intel 945G 24F

DFI Infinity NF4 SLI NVIDIA nForce4 SLI 2006/04/10

DFI

LANPARTY UT

nF4 Ultra-D

NVIDIA nForce4

Ultra 4/6/2006

ECS 945P-A Intel 945P 2.58 10/18/05

ECS KN1 SLI Lite NVIDIA nForce4

Ultra 1.1d

ECS nForce4-A939 NVIDIA nForce4 1.1g

120

EVGA

123-K8-NF47-

AX NVIDIA nForce4 SLI

04/11/2006-NF-

CK804-

6A61FJ1AC-00

Foxconn

NF4SLI7AA-

8EKRS2

NVIDIA nForce4 SLI

Intel Ed. 537F1P34

Foxconn

C51XEM2AA-

8EKRS2H

NVIDIA nForce 590

SLI 612W1P19

Gigabyte

GA-81945GMH-

RH Intel 945G F3

Gigabyte GA-8I945P-G Intel 945P F5

Gigabyte GA-8I945P PRO Intel 945P F5

Gigabyte

GA-8N-SLI (Rev

1.0)

NVIDIA nForce SLI

Intel Ed. F5

Gigabyte

GA-8N-SLI

(Rev1.1)

NVIDIA nForce SLI

Intel Ed. F5

Gigabyte

GA-8N-SLI-

Quad Royal

NVIDIA nForce4 SLI

Intel Ed. F5

Gigabyte

GA-8N-SLI

Royal

NVIDIA nForce SLI

Intel Ed. F6

Gigabyte GA-965P-DQ6 Intel 965P F2

Gigabyte GA-K8N Pro-SLI NVIDIA nForce4 SLI F4

Gigabyte GA-K8N-SLI NVIDIA nForce4 SLI F9

Gigabyte GA-K8N51GMF NVIDIA nForce F7

121

410/GeForce 6100

Gigabyte

GA-

K8N51PVM9-RH

NVIDIA nForce

430/GeForce 6150 F1

Gigabyte GA-K8NE NVIDIA nForce4 FB

Gigabyte GA-K8NF-9 NVIDIA nForce4 F10

Gigabyte GA-K8N-SLI NVIDIA nForce4 SLI F9

Gigabyte GA-K8NXP-9 NVIDIA nForce4

Ultra F9

Gigabyte GA-K8NXP-SLI NVIDIA nForce4 SLI F11

Gigabyte GA-M59SLI-S5 NVIDIA nForce 590

SLI D8

Intel D955XBK Intel 955X 2036

Intel D975XBX Intel 975X 1073

Intel SE7525GP2 Intel E7525 P08

iWill DK8EW 59102 NVIDIA nForce4 Pro

2200 V130

Jetway 939GT4-SLI-G NVIDIA nForce4 SLI 6/24/2006

MSI

K8N Diamond

Plus NVIDIA nForce4 SLI 1.2

MSI K8N Neo3 NVIDIA nForce4 1.5

MSI K8N Neo4 NVIDIA nForce4 1.D

122

Platinum v1 Ultra

MSI

K9N-SLI

Platinum

NVIDIA nForce 570

SLI 1.1

MSI P4N Diamond NVIDIA nForce4 SLI

Intel Edition 1.4

MSI 945P NEO2-F Intel 945P A7176IMS v3.2

12/12/05

Shuttle

XPC Barebone

Systems

Check

Manufacturer's

Website

Supermicro X6DA8 Intel E7525 1.0B

Tyan S2895 D/T NVIDIA nForce

2200/2050 2895_103k

MEMORY

Memory cards are a popular storage medium for many of today's consumer

electronics devices, including digital cameras, cell phones, handheld devices and other

small electronic devices. Flash memory is non-volatile that is the memory card will not

lose its data when removed from the device, and the cards can also be erased or

reformatted and reused.

For most consumers, when buying a memory card you have to consider price, capacity

and compatibility. Some devices will support up to a specific size of memory card, and a

specific type of memory card as well. Its important to read the information that came

with your device to ensure you purchase a memory card that will work in your device.

There are a few major types of memory cards that can be used in common electronics,

such as a digital camera. Each of these types of memory cards are different sizes and,

as the technology progresses further, we see that over time the cards have become

smaller in physical size but grow larger in logical size.

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Common Types of Memory Cards

CompactFlash (CF)

Invented by SanDisk Corporation in 1994, CompactFlash cards can support 3.3V and

5V operation and can switch between the two, in contrast to other small-form factor

flash memory cards that can operate only at one voltage. The card was designed based

on the PCMCIA PC Card standard and can fit into a PCMCIA slot with an adapter.

There are two types of CompactFlash cards to accommodate different capacities:

Type I cards are 42.8mm x 36.4mm x 3.3 mm thick

Type II cards are 42.8mm x 36.4mm x 5.5 mm thick.

Secure Digital Card (SD card)

SD cards are used in many small portable devices such as digital video camcorders,

digital cameras, handheld computers, audio players and mobile phones. In use since

1999, SD Memory Cards are now available in capacities between 16 Megabytes and 1

Gigabyte, and still growing. An SD card typically measures 32 mm x 24 mm x 2.1 mm

and weighs approximately 2grams.

MiniSD Card

After the success of the SD Card (Secure Digital Card), the miniSD Memory Card was

developed to meet the demands of the mobile phone market. The MiniSD Card provides

the same benefits as the SD Card, but is smaller than the original SD Card. MiniSD

Cards are typically found in many newer mobile phones with features such as built-in

digital cameras, downloading and games, basically the mobile phones where the

miniSD can meet the requirements for increased data storage. MiniSD cards are 21.5

mm x 20 mm x 1.4 mm and generally provide 16MB to 256MB of storage.

MicroSD

Mainly used in mobile phones and other small handheld devices the MicroSD format is

currently available in capacities up to 4GB, and it roughly 1/4th the size of the SD card

at 15mm W 11mm W 0.7mm. The MicroSD card is also the smallest memory card

available.

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Card adapters can be purchased that enable backwards compatibility — this would

allow MicroSD cards to work in SD and MiniSD slots, and also for MicroSD cards to

work in SD card slots.

MultiMediaCard (MMC)

The MultiMediaCard (MMC) standard was introduced by SanDisk and Siemens in 1997.

The card itself is 32 mm x 24 mm x 1.4mm and is often used in place of the SD card.

Transfer speeds of a MMC is around 2.5MB/s and they can often be used in SD Card

readers.

Sony Memory Sticks

Sony Memory Sticks are light, compact and designed for a wide variety of devices

including digital cameras, recorders, and more. With the use of an adapter most Sony

Memory Sticks can be used with almost all Memory Stick

PRO compatible products.

Memory Stick Micro (M2): 15 mm x 12.5 mm x 1.2 mm

Memory Stick PRO: 50 mm x 21.5 mm x 2.8 mm. The Memory Stick PRO format has an an 8-bit parallel interface with theoretical transfer rates up to 480Mb/s. It is commonly used in high megapixel digital cameras and digital camcorders.

Memory Stick PRO DUO: 31 mm x 20 mm x 1.6 mm. The Memory Stick PRO Duo media is about one-third the volume and half the weight of standard-size media, but offers all the advanced functions of Memory Stick PRO media.

Smart Media

Introduced by Toshiba in 1995 the Smart Media cards are now considered obsolete

despite its popular usage for five years. Smart Media cards are 45 mm x 37 mm x 0.76

mm and could be found in their peak times in 16MB, 32MB, and 128MB versions. Even

as an obsolete card, it is still sought after by users of older devices which cannot use

memory cards larger than 128MB.

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xD-Picture Card

Abbreviated as xD (Extreme Digital), the xD-Picture Card is a type of removable flash

memory designed for use in digital cameras. The xD is ultra-compact with its size of

20mm x 25mm x 1.7mm. The xD-Picture Card was developed by Fuji film and Olympus

and is used in many models of digital cameras made by Olympus and Fujifilm.

RANDOM ACCESS MEMORY (RAM)

Random-access memory (RAM ) is a form of computer data storage. A random-access memory device allows data items to be read and written in roughly the same amount of time regardless of the order in which data items are accessed. In contrast, with other direct-access data storage media such as hard disks, CD-RWs, DVD-RWs and the older drum memory, the time required to read and write data items varies significantly depending on their physical locations on the recording medium, due to mechanical limitations such as media rotation speeds and arm movement delays.

Today, random-access memory takes the form of integrated circuits. However, many types of SRAM are still random access even in a strict sense. RAM is normally associated with volatile types of memory (such as DRAM memory modules), where stored information is lost if the power is removed, although many efforts have been made to develop non-volatile RAM chips. Other types of non-volatile memory exist that allow random access for read operations, but either do not allow write operations or have limitations on them. These include most types of ROM and a type of flash memory called NOR-Flash.

Integrated-circuit RAM chips came into the market in the late 1960s, with the first commercially available DRAM chip, the Intel 1103, introduced in October 1970.

Different RAM Types and Its Uses

The letters RAM stand for “random access memory.” This memory is where your computer stores information about programs it is currently running. It is faster than writing and reading information from the hard drive because it has no physical components that need to move, just electrical signals. There are many different types of RAM and over time they have increased in speed and efficiency. There are two main types of RAM: volatile and non-volatile. Among volatile RAM, there are two subcategories: static and dynamic.

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SDRAM (Synchronous DRAM)

Almost all systems used to ship with 3.3 volt, 168-pin SDRAM DIMMs. SDRAM is not an extension of older EDO DRAM but a new type of DRAM altogether. SDRAM started out running at 66 MHz, while older fast page mode DRAM and EDO max out at 50 MHz. SDRAM is able to scale to 133 MHz (PC133) officially, and unofficially up to 180MHz or higher. As processors get faster, new generations of memory such as DDR and RDRAM are required to get proper performance.

DDR (Double Data Rate SDRAM)

DDR basically doubles the rate of data transfer of standard SDRAM by transferring data on the up and down tick of a clock cycle. DDR memory operating at 333MHz actually operates at 166MHz * 2 (aka PC333 / PC2700) or 133MHz*2 (PC266 / PC2100). DDR is a 2.5 volt technology that uses 184 pins in its DIMMs. It is incompatible with SDRAM physically, but uses a similar parallel bus, making it easier to implement than RDRAM, which is a different technology.

From the top: SIMM, DIMM and SODIMM memory modules

READ ONLY MEMORY

Read-only memory (ROM) is a class of storage medium used in computers and other electronic devices. Data stored in ROM can only be modified slowly or with difficulty, or not at all, so it is mainly used to distribute firmware (software that is very closely tied to specific hardware, and unlikely to need frequent updates).

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Strictly, read-only memory refers to memory that is hard-wired, such as diode matrix and the later mask ROM. Although discrete circuits can be altered (in principle), ICs cannot and are useless if the data is bad. The fact that such memory can never be changed is a large drawback; more recently, ROM commonly refers to memory that is read-only in normal operation, while reserving the fact of some possible way to change it.

Other types of non-volatile memory such as erasable programmable read only memory (EPROM) and electrically erasable programmable read-only memory (EEPROM or Flash ROM) are sometimes referred to, in an abbreviated way, as "read-only memory" (ROM); although these types of memory can be erased and re-programmed multiple times, writing to this memory takes longer and may require different procedures than reading the memory. When used in this less precise way, "ROM" indicates a non-volatile memory which serves functions typically provided by mask ROM, such as storage of program code and nonvolatile data.

TYPES OF ROM

Semiconductor Based

Classic mask-programmed ROM chips are integrated circuits that physically encode the data to be stored, and thus it is impossible to change their contents after fabrication. Other types of non-volatile solid-state memory permit some degree of modification:

Programmable read-only memory (PROM), or one-time programmable ROM (OTP), can be written to or programmed via a special device called a PROM programmer. Typically, this device uses high voltages to permanently destroy or create internal links (fuses or anti-fuses) within the chip. Consequently, a PROM can only be programmed once.

Erasable programmable read-only memory (EPROM) can be erased by exposure to strong ultraviolet light (typically for 10 minutes or longer), then rewritten with a process that again needs higher than usual voltage applied. Repeated exposure to UV light will eventually wear out an EPROM, but the endurance of most EPROM chips exceeds 1000 cycles of erasing and reprogramming. EPROM chip packages can often be identified by the prominent quartz "window" which allows UV light to enter. After programming, the window is typically covered with a label to prevent accidental erasure. Some EPROM chips are factory-erased before they are packaged, and include no window; these are effectively PROM.

Electrically erasable programmable read-only memory (EEPROM) is based on a similar semiconductor structure to EPROM, but allows its entire contents (or

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selectedbanks) to be electrically erased, then rewritten electrically, so that they need not be removed from the computer (or camera, MP3 player, etc.). Writing or flashing an EEPROM is much slower (milliseconds per bit) than reading from a ROM or writing to a RAM (nanoseconds in both cases).

Electrically alterable read-only memory (EAROM) is a type of EEPROM that can be modified one bit at a time. Writing is a very slow process and again needs higher voltage (usually around 12 V) than is used for read access. EAROMs are intended for applications that require infrequent and only partial rewriting. EAROM may be used as non-volatile storage for critical system setup information; in many applications, EAROM has been supplanted by CMOS RAM supplied by mains power and backed-up with a lithium battery.

Flash memory (or simply flash) is a modern type of EEPROM invented in 1984. Flash memory can be erased and rewritten faster than ordinary EEPROM, and newer designs feature very high endurance (exceeding 1,000,000 cycles). Modern NAND flash makes efficient use of silicon chip area, resulting in individual ICs with a capacity as high as 32 GB as of 2007; this feature, along with its endurance and physical durability, has allowed NAND flash to replace magnetic in some applications (such as USB flash drives). Flash memory is sometimes called flash ROM or flash EEPROM when used as a replacement for older ROM types, but not in applications that take advantage of its ability to be modified quickly and frequently.

By applying write protection, some types of reprogrammable ROMs may temporarily become read-only memory.

SYSTEM BUS

A system bus is a single computer bus that connects the major components of a computer system. The technique was developed to reduce costs and improve modularity. It combines the functions of a data bus to carry information, an address bus to determine where it should be sent, and a control bus to determine its operation. Although popular in the 1970s and 1980s, modern computers use a variety of separate buses adapted to more specific needs.

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ISA - INDUSTRY STANDARD ARCHITECHTURE

Industry Standard Architecture (ISA) is a retronym term for the 16-bit internal bus of IBM PC/AT and similar computers based on the Intel 80286 and its immediate successors during the 1980s. The bus was (largely) backward compatible with the 8-bit bus of the8088-based IBM PC, including the IBM PC/XT as well as IBM PC compatibles.

Originally referred to as the PC/AT-bus it was also termed I/O Channel by IBM. The ISA concept was coined by competing PC-clone manufacturers in the late 1980s or early 1990s as a reaction to IBM attempts to replace the AT-bus with its new and incompatible Micro Channel architecture.

The 16-bit ISA bus was used also with 32-bit processors for several years. An attempt to extend it to 32 bits, called Extended Industry Standard Architecture (EISA), was not very successful, however. Later buses such as VESA Local Bus and PCI were used instead, often along with ISA slots on the same mainboard. A derivative of the AT bus structure is still used in the PCMCIA standard, Compact Flash, the PC/104 bus, and internally within Super I/O chips.

ISA BUS

• Introduced by IBM, ISA or Industry Standard Architecture was originally an 8-bit bus that was later expanded to a 16-bit bus in 1984.

• In 1993, Intel and Microsoft introduced a PnP ISA bus that allowed the computer to automatically detect and setup computer ISA peripherals such as a modem or sound card.

• Using the PnP technology an end-user would have the capability of connecting a device and not having to configure the device using jumpers or dipswitches.

• Many manufacturers are trying to eliminate the usage of the SA slots however for backwards compatibility you may find 1 or 2 ISA slots with additional PCI slots.

EISA - EXTENDED INDUSTRY STANDARD ARCHITECTURE

The Extended Industry Standard Architecture (in practice almost always shortened to EISA and frequently pronounced "eee-suh") is a bus standard for IBM PC compatible computers. It was announced in September 1988 by a consortium of PC clone vendors (the "Gang of Nine") as a counter to IBM's use of its proprietary Micro Channel architecture (MCA) in its PS/2 series.

EISA extends the AT bus, which the Gang of Nine retroactively renamed to the ISA bus to avoid

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infringing IBM's trademark on its PC/AT computer, to 32 bits and allows more than one CPU to share the bus. The bus mastering support is also enhanced to provide access to 4 GB of memory. Unlike MCA, EISA can accept older XT and ISA boards — the lines and slots for EISA are a superset of ISA.

EISA was much favored by manufacturers due to the proprietary nature of MCA, and even IBM produced some machines supporting it. It was somewhat expensive to implement (though not as much as MCA), so it never became particularly popular in desktop PCs. However, it was reasonably successful in the server market, as it was better suited to bandwidth-intensive tasks (such as disk access and networking). Most EISA cards produced were either SCSI or network cards. EISA was also available on some non-IBM compatible machines such as the Alpha Server, HP 9000-D, SGI Indigo2 and MIPS Magnum.

By the time there was a strong market need for a bus of these speeds and capabilities for desktop computers, the VESA Local Bus and later PCI filled this niche and EISA vanished into obscurity.

EISA Bus

Extended ISA (EISA) has a 32-bit data bus but still operates at 8MHz.

It is rarely used -- mainly as a disk controller or video graphics adapter.

New pins for EISA bus are interspersed with the older pins in the 16-bit ISA connector to preserve compatibility with the old standard.

Most of the new EISA connections are used for the 32-bit data and 32-bit latched address bus.

PCI

Short for Peripheral Component Interconnect, PCI was introduced by Intel in1992, revised in 1993 to version 2.0, and later revised in 1995 to PCI 2.1 and is as an expansion to the ISA bus. The PCI bus is a 32-bit (133MBps) computer bus that is also available as a 64-bit bus and was the most commonly found and used computer bus in computers during the late 1990's and early 2000's. Unlike, ISA and earlier expansion a card, PCI follows the PnP specification and therefore does not require any type of jumpers or dip switches. Below is an example of what the PCI slots looks like on a motherboard. In the picture, there are three PCI slots, PCI4, PCI5, and PCI6.

PCI BUS

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- Introduced by Intel in 1992, PCI is short for Peripheral Component Interconnect and is a 32-bit computer bus that is also available as a 64-bit bus today. The PCI bus is the most commonly used and found bus in computers today.

- Mini PCI is a new standard developed by leading notebook manufactures. This technology could allow manufactures to lower their price as the motherboards would be simpler to design.

- PCI-X is a high performance bus that is designed to meet th increased I/O demands of technologies such as Fibber Channel, Gigabit Ethernet and Ultra3 SCSI. PCI-X capabilities include:

o Up to 133 MHz bus speed o 64-Bit bandwidth

o 1GB/sec throughput

AGP

Short for Accelerated

Graphics Port, AGP is an

advanced port designed

for Video cards and 3D

accelerators. Designed by Intel and introduced in August of 1997, AGP introduces a

dedicated point-to-point channel that allows the graphics controller direct access the

system memory. Below is an illustration of what the AGP slot may look like on

your motherboard.

The AGP channel is 32-bits wide and runs at 66 MHz. This translates into a total

bandwidth of 266 MBps, which is much greater than the PCI bandwidth of up to

133 MBps. AGP also supports two optional faster modes, with throughput of 533 MBps

and 1.07 GBps. It also allows 3-D textures to be stored in main memory rather than

video memory.

Each computer with AGP support will either have one AGP slot or on-board AGP video.

If you needed more than one video card in the computer, you can have one AGP video

card and one PCI video card or use a motherboard that supports SLI.

AGP is available in three different versions, the original AGP version mentioned

above, AGP 2.0 that was introduced in May of 1998, and AGP 3.0 (AGP 8x) that was

introduced in November of 2000. AGP 2.0 added 4x signalling and was capable of

operating at 1.5V and AGP 3.0 was capable of double the transfer speeds.

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Tip: Not all operating systems support AGP because of limited or no driver support. For

example, Windows 95 did not incorporate AGP support. See the Windows versions

page for information about Windows versions that support AGP.

What is AGP Pro?

AGP Pro is an AGP interface extension specification for advanced workstations. This

specification delivers additional power to video cards, includes an extended connector,

thermal envelope, updated mechanical specifications, I/O bracket, and motherboard

layout requirements.

AGP

- Introduced by Intel in 1997, AGP or Advanced Graphic Port is a 32-bit bus designed for the high demands of 3-D graphics.

- AGP has a direct line to the computers memory which allows 3- D elements to be stored in the system memory instead of the video memory.

- For AGP to work in a computer must have the AGP slot which comes with most Pentium II and Pentium III machines.

- The computer also needs to be running Windows 95 OSR2.1, Windows 98, Windows 98 SE, Windows 2000, Windows ME or higher.

MCA - Micro Channel Architecture

It stands for "Micro Channel Architecture." It is an expansion bus created by IBM that was used in the company's PS/2 desktop computers. An expansion bus allows additional cards to be connected to the computer's motherboard, expanding the number of I/O ports. These include SCSI, USB, Fire wire, AGP, and DVI connections, as well as many others.

The MCA standard was designed to take the place of the AT and ISA buses used in previous IBM PC/AT compatible computers. While the MCA bus architecture was an improvement in both size and speed over AT and ISA, it was kept as a proprietary standard by IBM. This discouraged other manufacturers from adopting the standard, since the MCA architecture was not compatible with other standards. Most PC companies incorporated the more universal PCI and AGP expansion buses into their computers, which are both widely used today.

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USB - Universal Serial Bus

Universal Serial Bus (USB) is an industry standard developed in the mid-1990s that defines the cables, connectors and communications protocols used in a bus for connection, communication, and power supply between computers and electronic devices.

USB was designed to standardize the connection of computer peripherals (including keyboards, pointing devices, digital cameras, printers, portable media players, disk drives and network adapters) to personal computers, both to communicate and to supply electric power. It has become commonplace on other devices, such as smartphones, PDAs and video game consoles. USB has effectively replaced a variety of earlier interfaces, such as serial and parallel ports, as well as separate power chargers for portable devices.

Universal Serial Bus is a new external bus developed by Intel,

- Compaq, DEC, IBM, Microsoft, NEC and Northern Telcom and released to the public in 1996 with the Intel 430HX Triton II Mother Board.

- USB has the capability of transferring 12 Mbps, supporting up to 127 devices and only utilizing one IRQ.

- For PC computers to take advantage of USB the user must be running Windows 95 OSR2, Windows 98 or Windows 2000. Linux users also have the capability of running USB with the proper support drivers installed.

USB VERSIONS

- USB 1.0 - The original release of USB supports 127 devices transferring 12 Mbps.

- USB 1.1 - Also known as full-speed USB, USB 1.1 is similar to the original release of USB however minor modifications for the hardware and the specifications. This version of USB still only supports a rate of 12 Mbps.

- USB 2.0 - USB 2.0 also known as hi-speed USB was developed by Compaq, Hewlett Packard, Intel, Lucent, Microsoft, NEC and Philips and was introduced in 2001. Hi speed USB is capable of supporting a transfer rate of up to 480 Mbps and is

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backwards compatible meaning it is capable of supporting USB 1.0 and 1.1 devices and cables.

CMOS

Complementary metal-oxide-semiconductor (CMOS is a technology for constructing integrated circuits. CMOS technology is used in microprocessors, microcontrollers, static RAM, and other digital logic circuits. CMOS technology is also used for several analogue circuits such as image sensors (CMOS sensor), data converters, and highly integrated transceivers for many types of communication. Frank Wanlass patented CMOS in 1963 (US patent 3,356,858).

CMOS is also sometimes referred to as complementary-symmetry metal–oxide–semiconductor (or COS-MOS). The words "complementary-symmetry" refer to the fact that the typical digital design style with CMOS uses complementary and symmetrical pairs of p-type and n-type metal oxide semiconductor field effect transistors (MOSFETs) for logic functions.

Two important characteristics of CMOS devices are high noise immunity and low static power consumption. Since one transistor of the pair is always off, the series combination draws significant power only momentarily during switching between on and off states. Consequently, CMOS devices do not produce as much waste heat as other forms of logic, for example transistor–transistor logic (TTL) or NMOS logic, which normally have some standing current even when not changing state. CMOS also allows a high density of logic functions on a chip. It was primarily for this reason that CMOS became the most used technology to be implemented in VLSI chips.

The phrase "metal–oxide–semiconductor" is a reference to the physical structure of certain field-effect transistors, having a metal gate electrode placed on top of an oxide

insulator, which in turn is on top of a semiconductor material. Aluminium was once used but now the material is poly silicon. Other metal gates have made a comeback with the advent of high-k dielectric materials in the CMOS process, as announced by IBM and Intel for the 45 nanometer node and beyond.

Alternatively referred to as a Real-Time Clock

(RTC), Non-Volatile RAM (NVRAM) or CMOS

RAM, CMOS is short for Complementary Metal-

Oxide Semiconductor. CMOS is an on-board

semiconductor chip powered by a CMOS battery

inside computers that stores information such as

the system time and date and the system hardware

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settings for your computer. The picture shows an example of the most common CMOS

coin cell battery used in a computer to power the CMOS memory.

A Motorola 146818 chip was the first RTC and CMOS RAM chip to be used in early IBM computers. The chip was capable of storing a total of 64 bytes of data. Since the system clock used 14 bytes of RAM, this left an additional 50 bytes of space that was available for IBM to store system settings. Today, most computers have moved the settings from a separate chip and incorporated them into the south bridge or Super I/O chips.

The CMOS is also a computer chip on the motherboard, but more specifically, it is

a RAM chip. This is a type of memory chip which stores information about the computer

components, as well as settings for those components. However, normal RAM chips

lose the information stored in them when power is no longer supplied to them. In order

to retain the information in the CMOS chip, a CMOS battery on the motherboard

supplies constant power to that CMOS chip. If the battery is removed from the

motherboard or runs out of juice (e.g. a dead CMOS battery), the CMOS would lose the

information stored in it. Any settings you made in the CMOS setup would be lost, and

you would need to make those settings changes again after a new CMOS battery was

put on the motherboard. For example, with a dead CMOS battery the time and date will

reset back to the manufactured date if it has been off for a long period of time.

The BIOS program on the BIOS chip reads information from the CMOS chip when the

computer is starting up, during the boot up process. You may notice on the initial start

up screen, called the POST screen, an option is available to enter the BIOS or CMOS

setup. When you enter this setup area, you are entering the CMOS setup, not the BIOS

setup. The BIOS chip and program cannot be updated directly by a user. The only way

to update the BIOS is using a BIOS flash program called a BIOS update, which updates

the BIOS to a different version. These updates usually are provided by either the

motherboard manufacturer or the computer manufacturer.

The CMOS setup lets you change the time and date and settings for how devices are

loaded at start up, like hard drives, disc drives, and floppy drives. The CMOS setup lets

you enable and disable various hardware devices, including USB ports, the onboard

video card and sound card (if present), parallel and serial ports, and other devices.

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POST - POWER ON SELF TEST

A power-on self-test (POST) is a process performed by firmware or software routines immediately after a computer or other digital electronic device is powered on.

This article mainly deals with personal computers, but many other embedded systems such as those in major appliances, avionics, communications, or medical equipment also have self-test routines which are automatically invoked at power-on.

The results of tests run by the POST may be displayed on a panel that is part of the device, output to an external device, or stored for future retrieval by a diagnostic tool. Since a self-test might detect that the system's usual human-readable display is non-functional, an indicator lamp or a speaker may be provided to show error codes as a sequence of flashes or beeps. In addition to running tests, the POST process may also set the initial state of the device from firmware.

In the case of a computer, the POST routines are part of a device's pre-boot sequence and only once they complete successfully is the bootstrap loader code invoked to load an operating system.

- The Power-On Self Test (POST) is a special program stored on the ROM chip o Initiated when the computer is turned on, or is reset o Checks out the system every time the computer boots

- The computer power-on self-test (POST) tests the computer to make sure it

meets the necessary system requirements and that all hardware is working

properly before starting the remainder of the boot process. If the computer

passes the POST the computer gives a single beep (with some

computer BIOS manufacturers it may beep twice) as the computer starts and the

computer will continue to start normally. However, if the computer fails the POST,

the computer will either not beep at all or will generate a beep code, which tells

the user the source of the problem.

- Abbreviated as POST, the Power On Self Test is the initial set of diagnostic tests

performed by the computer when powered on.

- Tests that fail are relayed to the user via the use ofPOST codes, beep codes or

on-screen POST error messages immediately after the computer powers on.

- The POST is handled by the system's BIOS.

- Short for power-on self-test, the POST is a test the computer must complete to

verify all hardware is working properly before starting the remainder of the boot

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process. If the computer passes the POST the computer may return a single

beep and if unsuccessful generate a beep code to indicate the error and not

boot.

POST Cards

- POST cards are devices that monitor POSTs and report on the hardware that may be causing problems

o Turn the PC off, plug in the card, and reboot o POST error codes do not fix the computer – they just tell you where to

look o If all else fails, replace the motherboard

SETUP

Standard CMOS Setup

In the Standard CMOS menu you can set the system clock and calendar, record disk drive parameters and the video subsystem type, and select the type of errors that stop the BIOS POST.

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DATE

The BIOS determines the day of the week from the other date

information.

This field is for information only.

Press the ® or ¬ key to move to the desired field (date, month, year).

Press the PgUp or PgDn key to increment the setting, or type the

desired value into the field.

TIME

The time format is based on the 24-hour military-time clock. For

example, 1 p.m. is 13:00:00.

Press the ® or ¬ key to move to the desired field. Press the PgUp or

PgDn key to increment the setting, or type the desired value into the

field.

DAYLIGHT

SAVING

This category may not be present in your Setup program. When

enabled, it adds one hour to the clock when daylight-saving time

begins. It also subtracts one hour when standard time returns.

HARD

DISKS

The BIOS supports up to four IDE drives. This section does not show

information about other IDE devices, such as a CD-ROM drive, or

about other hard drive types, such as SCSI drives.

NOTE: We recommend that you select type AUTO for all drives.

The BIOS can automatically detect the specifications and optimal operating mode of almost all IDE hard drives. When you select type AUTO for a hard drive, the BIOS detects its specifications during POST, every time the system boots.

If you do not want to select drive type AUTO, other methods of selecting the drive type are available:

- Match the specifications of your installed IDE hard drive(s) with the pre- programmed values for drive types 1 through 45.

- Select USER and enter values into each drive parameter field. - Use the IDE HDD AUTO DECTECTION function in Setup.

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CHIPSET

- In a computer system, a chipset is a set of electronic components in an integrated circuit that manages the data flow between the processor, memory and peripherals. It is usually found on the motherboard. Chipsets are usually designed to work with a specific family of microprocessors. Because it controls communications between the processor and external devices, the chipset plays a crucial role in determining system performance.

- Mobile phones run on so-called embedded chipsets, which are designed to perform one or a few dedicated functions, often with real-time computing constraints. They are embedded as part of the complete device including hardware and mechanical parts.

The ever popular smartphones are equipped with more advanced embedded chipsets that can do many different tasks depending on their programming.

Thus their CPU (Central Processing Unit) performance is vital for the daily user experience and people tend to use the clock rate of the main CPU that's in the heart of the chipset to compare the performance of competing end products.

As we already pointed out, the clock rate of a processor is only useful for providing performance comparisons between computer chips in the same processor family and generation.

Also, as mobile gaming is increasingly gaining popularity, users have become more aware of the various types of GPU (Graphics Processing Unit) chips that come as part of the mobile chipsets and sometimes even consider their performance when making buying decisions.

Northbridge

A Northbridge or host bridge is a microchip on some PC motherboards and is

connected directly to the CPU (unlike the Southbridge) and thus responsible for tasks

that require the highest performance. The Northbridge is usually paired with a south

bridge, also known as I/O controller hub. In systems where they are included, these two

chips manage communications between the CPU and other parts of the motherboard,

and constitute the core logic chipset of the PC motherboard.

On older Intel based PCs, the Northbridge was also named external memory controller

hub (MCH) or integrated memory controller hub(IMCH) if equipped with an integrated

VGA memory controller hub(MCH). Increasingly these functions became integrated into

the CPU chip itself, beginning with memory and graphics controllers. For Intel Sandy

Bridge and AMD Accelerated Processing Unit processors introduced in 2011, all of the

functions of the Northbridge reside on the CPU, while some high-performance CPUs

still (2013) require Northbridge and Southbridge chips.

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Separating the different functions into the CPU, Northbridge, and Southbridge chips was

due to the difficulty of integrating all components onto a single chip. In some instances,

the Northbridge and Southbridge functions have been combined onto one die when

design complexity and fabrication processes permitted it; for example, the

Nvidia GeForce 320M in the 2010 MacBook Air is a Northbridge/Southbridge/GPU

combo chip.

As CPU speeds increased, a bottleneck eventually emerged between the processor and

the motherboard, due to limitations caused by data transmission between the CPU and

its support chipset. Accordingly, starting with the AMD Athlon64 series CPUs (based on

the Opteron), a new architecture was used where some functions of the north- and

southbridge chips were moved to the CPU. Modern Intel Core processors have the

northbridge integrated on the CPU die as the system agent.

Overview

The northbridge typically handles communications among the CPU, in some

cases RAM, and PCI Express (or AGP) video cards, and the southbridge. Some

northbridges also contain integrated video controllers, also known as a Graphics and

Memory Controller Hub (GMCH) in Intel systems. Because different processors and

RAM require different signaling, a given northbridge will typically work with only one or

two classes of CPUs and generally only one type of RAM.

There are a few chipsets that support two types of RAM (generally these are available

when there is a shift to a new standard). For example, the northbridge from

the Nvidia nForce2 chipset will only work with Socket A processors combined with DDR

SDRAM; the Intel i875 chipset will only work with systems using Pentium 4 processors

or Celeron processors that have a clock speed greater than 1.3 GHz and utilize DDR

SDRAM, and the Intel i915g chipset only works with the Intel Pentium 4 and the

Celeron, but it can use DDR or DDR2 memory.

Etymology

The name is derived from drawing the architecture in the fashion of a map. The CPU

would be at the top of the map comparable to due north on most general purpose

geographical maps. The CPU would be connected to the chipset via a fast bridge (the

northbridge) located north of other system devices as drawn. The northbridge would

then be connected to the rest of the chipset via a slow bridge (the southbridge) located

south of other system devices as drawn.

Overclocking

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The northbridge plays an important part in how far a computer can be overclocked, as

its frequency is commonly used as a baseline for the CPU to establish its own operating

frequency. This chip typically gets hotter as processor speed becomes faster, requiring

more cooling. There is a limit to CPU overclocking, as digital circuitsare limited by

physical factors such as propagation delay which increases with (among other

factors) operating temperature; consequently most overclocking applications have

software-imposed limits on the multiplier and external clock setting.

Evolution

The overall trend in processor design has been to integrate more functions onto fewer

components, which decreases overall motherboard cost and improves performance.

The memory controller, which handles communication between the CPU and RAM, was

moved onto the processor die by AMD beginning with their AMD64processors and by

Intel with their Nehalem processors. One of the advantages of having the memory

controller integrated on the CPU die is to reduce latency from the CPU to memory.

Another example of this kind of change is Nvidia's nForce3 for AMD64 systems. It

combines all of the features of a normal southbridge with an Accelerated Graphics

Port (AGP) port and connects directly to the CPU. On nForce4 boards it was marketed

as a media communications processor (MCP).

AMD Accelerated Processing Unit processors feature

full integration of northbridge functions onto the CPU

chip, along with processor cores, memory controller

and graphics processing unit (GPU). This was an

evolution of the AMD64, since the memory controller

was integrated on the CPU die in the AMD64.

The northbridge was replaced by the system agent

introduced by the Sandy Bridge microarchitecture in

2011, which essentially handles all previous

Northbridge functions. Intel’s “Sandy Bridge”

processors feature full integration of northbridge functions onto the CPU chip, along with

processor cores, memory controller and graphics processing unit (GPU). This was a

further evolution of the Westmere architecture, which also featured a CPU and GPU in

the same package.

NORTHBRIDGE

Alternatively referred to as the PAC (PCI/AGP Controller) and sometimes abbreviated

as nb, the northbridge is an integrated circuit that is responsible for communications

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between the CPU interface, AGP, and the memory. Unlike the Southbridge the

Northbridge is directly connected to these components and acts like a "bridge" for the

Southbridge chip to communicate with the CPU, RAM, and graphics controller. Today,

the northbridge is a single-chip that is North of the PCI bus, however, early computers

may have had up to three separate chips that made up the northbridge.

Below is a graphic illustration of the ASUS P5AD2-E motherboard and some basic

explanations of each of the major portions of the motherboard, including the

northbridge. As shown in the picture below, it's common for the northbridge and

southbridge to have a heat sink; in addition, the northbridge is usually slightly larger

than the southbridge and is the closest to the CPU and memory.

When the CPU needs data from RAM, a request is sent to the northbridge memory

controller. After the request has been received, it responds with how long the processor

need to wait in order to read the memory over the front side bus (FSB). Some newer

motherboards have replaced the northbridge and the southbridge with IHA.

My motherboard doesn't have a northbridge

As manufacturers look for new ways to improve performance and lower the overall cost

they are moving the functions of the northbridge chip to other parts of the CPU and

southbridge. Beginning with the AMD64 AMD and the Intel Nehalem processors the

memory controller was moved from the northbridge to the processor die. Later, the Intel

"Sandy Bridge" and the AMD Accelerated Processing Unit processors placed all

northbridge functions onto the CPU.

Northbridge

The high-speed part of a common chipset architecture in a computer. The Northbridge

is the controller that interconnects the CPU to memory via the frontside bus (FSB). It

also connects peripherals via high-speed channels such as AGP and PCI Express. The

Northbridge may include a display controller, obviating the need for a separate display

adapter.

The Southbridge controller handles the remaining I/O, including the PCI bus, parallel

and Serial ATA drives (IDE), USB, FireWire, serial and parallel ports and audio ports.

Earlier chipsets supported the ISA bus in the Southbridge. Starting with Intel's 8xx

chipsets, Northbridge and Southbridge were changed to Memory Controller and I/O

Controller.

Northbridge Connects CPU to:

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RAM

AGP bus

PCI Express bus

Built-in display Adapter

Southbridge Connects CPU to:

ATA (IDE) Drives

USB bus

FireWire bus

Serial port

Parallel port

Built-in audio

ISA bus (earlier PCs)

Southbridge

The southbridge is one of the two chips in the core logic chipset on apersonal

computer (PC) motherboard, the other being the northbridge. The southbridge typically

implements the slower capabilities of the motherboard in a

northbridge/southbridge chipset computer architecture. In Intel chipset systems, the

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southbridge is namedInput/Output Controller Hub (ICH). AMD, beginning with

its FusionAPUs, has given the label FCH, or Fusion Controller Hub, to its southbridge.

The southbridge can usually be distinguished from the northbridge by not being directly

connected to the CPU. Rather, the northbridge ties the southbridge to the CPU.

Through the use of controller integrated channel circuitry, the northbridge can directly

link signals from the I/O units to the CPU for data control and access.

Current status

Due to the push for system-on-a-chip (SoC) processors, modern devices increasingly

have the northbridge integrated into the CPU dieitself; examples are Intel's Sandy

Bridge and AMD's Fusion processors, both released in 2011. The southbridge became

redundant and it was replaced by the Platform Controller Hub (PCH) architecture

introduced with the Intel 5 Series chipset in 2008. All southbridge features and

remaining I/O functions are managed by the PCH which is directly connected to the

CPU via the Direct Media Interface (DMI).

Overview

A southbridge chipset handles all of a computer's I/O functions, such as USB, audio,

serial, the system BIOS, the ISA bus, the interrupt controller and the IDE

channels. Different combinations of Southbridge and Northbridge chips are possible, but

these two kinds of chips must be designed to work together; there is no industry-wide

standard for interoperability between different core logic chipset designs. Traditionally,

the interface between a northbridge and southbridge was the PCI bus. The main

bridging interfaces used now are DMI (Intel) and UMI (AMD).

Etymology

The name is derived from drawing the

architecture in the fashion of a map and was

first described as such with the introduction of

the PCI Local Bus Architecture in 1991. At

Intel, the authors of the PCI specification

viewed the PCI local bus as being at the very

centre of the PC platform architecture (i.e., at

the Equator).

The northbridge extends to the north of the PCI

bus backbone in support of CPU,

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Memory/Cache, and other performance-critical capabilities. Likewise the southbridge

extends to the south of the PCI bus backbone and bridges to less performance-critical

I/O capabilities such as the disk interface, audio, etc.

The CPU is located at the top of the map at due north. The CPU is connected to the

chipset via a fast bridge (thenorthbridge) located north of other system devices as

drawn. The northbridge is connected to the rest of the chipset via a slow bridge (the

southbridge) located south of other system devices as drawn.

Although the current PC platform architecture has replaced the PCI bus backbone with

faster I/O backbones, the bridge naming convention remains.

Functionality

Diagram of a modern motherboard, note the

lack of individual Northbridge and

Southbridge chips.

The functionality found in a contemporary

southbridge includes:

PCI bus. The PCI bus support

includes the traditional PCI specification, but

may also include support for PCI-X and PCI

Express.

ISA bus or LPC Bridge. Though the ISA support is rarely utilized, it has

interestingly managed to remain an integrated part of the modern southbridge.

The LPC Bridge provides a data and control path to the Super I/O (the normal

attachment for the keyboard, mouse, parallel port, serial port, IR port, and floppy

controller) and FWH (firmware hub which provides access

to BIOS flash storage).

SPI bus. The SPI bus is a simple serial bus mostly used

for firmware (e.g.,BIOS) flash storage access.

SMBus. The SMBus is used to communicate with other devices on the

motherboard (e.g., system temperature sensors, fan controllers).

DMA controller. The DMA controller allows ISA or LPC devices direct access

to main memory without needing help from the CPU.

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Interrupt controllers such as 8259A and/or I/O APIC. The interrupt controller

provides a mechanism for attached devices to get attention from the CPU.

Mass storage controllers such as PATA and/or SATA. This typically allows direct

attachment of system hard drives.

Real-time clock. The real time clock provides a persistent time account.

Power management (APM and ACPI). The APM or ACPI functions provide

methods and signaling to allow the computer to sleep or shut down to save

power.

Nonvolatile BIOS memory. The system CMOS (BIOS configuration memory),

assisted by battery supplemental power, creates a limited non-volatile storage

area for system configuration data.

AC'97 or Intel High Definition Audio sound interface.

Out-of-band management controller such as a BMC or HECI.

Optionally, a southbridge also includes support for Ethernet, RAID, USB,audio codec,

and FireWire. Where support is provided for non-USB keyboard, mouse, and serial

ports, a machine normally does so through a device referred to as a Super I/O; still

more rarely, a southbridge may directly support the keyboard, mouse, and serial ports.

Southbridge

The Southbridge is an integrated circuit on the motherboard that is responsible for

the hard drive controller, I/O controller and integrated hardware such as sound card,

video card if present on the motherboard, USB, PCI, ISA, IDE, BIOS, and Ethernet. The

southbridge gets its name for commonly being South of the PCI bus. Below is a graphic

illustration of the ASUSP5AD2-E motherboard and some basic explanations of each of

the major portions of the motherboard including the southbridge. As shown in the

picture below, it is common for the northbridge and southbridge to have a heatsink; in

addition, the northbridge is usually slightly larger than the southbridge.

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Although the southbridge handles most of the I/O devices, less prominent input/output

devices, such as a serial port, keyboard, and non-USB mouse are handled by the super

input/output (SIO).

Note: Some newer chipsets are combining the Southbridge and Super I/O chips into a

single chip and referring to this chip as the Super Southbridge chip. Some

manufacturers such as NVIDIA andSiS have even combined the Northbridge,

Southbridge, and Super I/O into a single chip.

Note: Newer motherboards are also replacing the northbridge and the southbridge

with IHA.

The heart and soul of the PC’s data processing is the CPU. But the processor is not

alone in the world, it communicates with the rest of the motherboard. There will be many

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new terms introduced in the following sections, so remember that you can find

definitions for all the abbreviations in the back of the guide.

Busses do the transfers

Data packets (of 8, 16, 32, 64 or more bits at a time) are constantly being moved back

and forth between the CPU and all the other components (RAM, hard disk, etc.). These

transfers are all done using busses.

The motherboard is designed around some vary powerful data channels (or pathways,

as they are also called). It is these busses which connect all the components to each

other.

Figure 41. The busses are the data channels which connect the PC’s components

together. Some are designed for small transfers, others for large ones.

Busses with varying capacities

There is not just one bus on a motherboard; there are several. But they are all

connected, so that data can run from one to another, and hence reach the farthest

corners of the motherboard.

We can say that a bus system is subdivided into several branches. Some of the PC

components work with enormous amounts of data, while others manage with much less.

For example, the keyboard only sends very few bytes per second, whereas the working

storage (RAM) can send and receive several gigabytes per second. So you can’t attach

RAM and the keyboard to the same bus.

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Two busses with different capacities (bandwidths) can be connected if we place a

controller between them. Such a controller is often called a bridge, since it functions as

a bridge between the two different traffic systems.

Figure 42. Bridges connect the various busses together.

The entire bus system starts close to the CPU, where the load (traffic) is greatest. From

here, the busses work outwards towards the other components. Closest to the CPU we

find the working storage. RAM is the component which has the very greatest data traffic,

and is therefore connected directly to the CPU by a particularly powerful bus. It is called

the front side bus (FSB) or (in older systems) the system bus.

Figure 43. The PC’s most important bus looks after the “heavy” traffic between the CPU

and RAM.

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The busses connecting the motherboard to the PC’s peripheral devices are called I/O

busses. They are managed by the controllers.

The chip set

The motherboard’s busses are regulated by a number of controllers. These are small

circuits which have been designed to look after a particular job, like moving data to and

from EIDE devices (hard disks, etc.).

A number of controllers are needed on a motherboard, as there are many different

types of hardware devices which all need to be able to communicate with each other.

Most of these controller functions are grouped together into a couple of large chips,

which together comprise the chip set.

Figure 44. The two chips which make up the chipset, and which connect the

motherboard’s busses.

The most widespread chipset architecture consists of two chips, usually called

the north and south bridges. This division applies to the most popular chipsets from VIA

and Intel. The north bridge and south bridge are connected by a powerful bus, which

sometimes is called a link channel:

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Figure 45. The north bridge and south bridge share the work of managing the data

traffic on the motherboard.

The north bridge

The north bridge is a controller which controls the flow of data between the CPU and

RAM, and to the AGP port.

In Fig. 46 you can see the north bridge, which has a large heat sink attached to it. It

gets hot because of the often very large amounts of data traffic which pass through it.

All around the north bridge you can see the devices it connects:

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Figure 46. The north bridge and its immediate surroundings. A lot of traffic runs through

the north bridge, hence the heat sink.

The AGP is actually an I/O port. It is used for the video card. In contrast to the other I/O

devices, the AGP port is connected directly to the north bridge, because it has to be as

close to the RAM as possible. The same goes for the PCI Express x16 port, which is the

replacement of AGP in new motherboards. But more on that later.

The south bridge

The south bridge incorporates a number of different controller functions. It looks after

the transfer of data to and from the hard disk and all the other I/O devices, and passes

this data into the link channel which connects to the north bridge.

In Fig. 44 you can clearly see that the south bridge is physically located close to the PCI

slots, which are used for I/O devices.

Figure 47. The chipset’s south bridge combines a number of controller functions into a

single chip.

The various chipset manufacturers

Originally it was basically only Intel who supplied the chipsets to be used in

motherboards. This was quite natural, since Intel knows everything about their own

CPU’s and can therefore produce chipsets which match them. But at the time the

Pentium II and III came out, other companies began to get involved in this market. The

Taiwanese company, VIA, today produces chipsets for both AMD and Intel processors,

and these are used in a large number of motherboards.

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Other companies (like SiS, nVidia, ATI and ALi) also produce chipsets, but these

haven’t (yet?) achieved widespread use. The CPU manufacturer, AMD, produces some

chipsets for their own CPU’s, but they also work together closely with VIA as the main

supplier for Athlon motherboards.

The Taiwanese company, VIA, has been a leader in the development of new chipsets in

recent years.

Since all data transfers are managed by the chipset’s two bridges, the chipset is the

most important individual component on the motherboard, and new chipsets are

constantly being developed.

The chipset determines the limits for clock frequencies, bus widths, etc. The chipset’s

built-in controllers are also responsible for connecting I/O devices like hard disks and

USB ports, thus the chipset also determines, in practise, which types of devices can be

connected to the PC.

The two chips which make up a typical chipset. Here we have VIA’s model P4X266A,

which was used in early motherboards for Pentium 4 processors.

Sound, network, and graphics in chipsets

Developments in recent years have led chipset manufacturers to attempt to place more

and more functions in the chipset.00000FFFFFFFFFFFFFFFFFFFF

These extra functions are typically:

Video card (integrated into the north bridge)

Sound card (in the south bridge)

Modem (in the south bridge)

Network and Firewire (in the south bridge)

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All these functions have traditionally been managed by separate devices, usually plug-in

cards, which connect to the PC. But it has been found that these functions can definitely

be incorporated into the chipset.

Southbridge

In Northbridge/Southbridge chipset architecture designs, theSouthbridge is the chip that

controls all of the computers I/Ofunctions, such as USB, audio, serial, the system BIOS,

the ISA bus, the interrupt controller and the IDE channels. In other words, all of the

functions of a processor except memory, PCI and AGP.

The Southbridge chip is one of two chips that control the functions of the chipset. The

other is the Northbridge. The Northbridge can consist of more than one discrete chips

while the Southbridge is typically only one discrete chip that rests on the

Northbridge��s PCI bus.

Motherboard with built-in sound functionality.

Intel has, for many years, managed to produce excellent network cards (Ethernet

10/100 Mbps); so it is only natural that they should integrate this functionality into their

chipsets.

Sound facilities in a chipset cannot be compared with “real” sound cards (like, for

example, Sound Blaster Audigy). But the sound functions work satisfactorily if you only

want to connect a couple of small speakers to the PC, and don’t expect perfect quality.

Figure 51. This PC has two sound cards installed, as shown in this Windows XP dialog

box. The VIA AC’97 is a sound card emulation which is built into the chipset.

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Many chipsets also come with a built-in video

card. The advantage is clear; you can save having a separate video card, which can

cost a $100 or more.

Again, the quality can’t be compared with what you get with a separate, high quality,

video card. But if you don’t particularly need support for multiple screens, DVI (for flat

screens), super 3D performance for games, or TV-out, the integrated graphics controller

can certainly do the job.

Figure 52. This PC uses a video card which is built into the Intel i810 chipset.

It is important that the integrated sound and graphics functions can be disabled, so that

you can replace them with a real sound or video card. The sound functions won’t cause

any problems; you can always ask Windows to use a particular sound card instead of

another one.

But the first Intel chipset with integrated graphics (the i810) did not allow for an extra

video card to be installed. That wasn’t very smart, because it meant users were locked

into using the built-in video card. In the subsequent chipset (i815), the problem was

resolved.

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SUMMARY:

Basic Computer Components and Peripherals

Monitor - a screen which displays an image generated by a computer.

There are 3 basic types of Monitor

1. Cathode Ray Tube (CRT) 2. Liquid Crystal Display ( LCD) 3. Light-Emitting Diode (LED)

Central Processing Unit (CPU) - It is the Brain of the Computer. The computer CPU is responsible for handling all instructions and calculation it receives from other hardware components in the computer and software programs running on the computer.

Motherboard - It is a printed circuit that is the foundation of a computer and allows the CPU, RAM, and all other computer hardware components to function with each other.

Memory - It is a term commonly used to describe the memory within a computer. It is a Storage Device.

Two Types of Computer Memory:

1. Random Access Memory (RAM) 2. Read Only Memory (ROM)

System Busses

- ISA ( Industry Standard Architecture) - EISA (Extended Industry Standard Architecture) - PCI (Peripheral Component Interconnect) - AGP (Accelerated Graphics Port) - MCA (Micro Channel Architecture) - USB (Universal Serial Bus)

CMOS - also known as complementary metal-oxide-semiconductor, CMOS is an on-board semiconductor chip powered by a CMOS battery inside computers that stores information such as the system time and date and the system hardware settings for your computer.

POST - also known as POWER ON SELF TEST. A power-on self-test (POST) is a process performed by firmware or software routines immediately after a computer or other digital electronic device is powered on.

Chipset - In a computer system, a chipset is a set of electronic components in an integrated circuit that manages the data flow between the processor, memory and peripherals. It is usually found on the motherboard.

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Northbridge - Northbridge is directly connected to these components and acts like a "bridge" for the Southbridge chip to communicate with the CPU, RAM, and graphics controller.

Southbridge - The Southbridge is an integrated circuit on the motherboard that is responsible for the hard drive controller, I/O controller and integrated hardware such as sound card,

Chapter Quiz

Essay

1. Explain the Types of Monitor. 2. Differences of LED monitor and LCD monitor. 3. Differences between RAM and ROM. 4. Explain the Northbridge and Southbridge.

***Good Luck!***

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NETWORK INTERFACE CARD (NIC)

Short for Network Interface Card, a NIC is also

commonly referred to as an Ethernet card and

network adapter and is an expansion card that

enables a computer to connect to a network

such as a home network or the Internet using

an Ethernet cable with a RJ-45 connector. The

picture is an example of a SMC EZ Card

10/100 PCI network card, a network card

commonly found in most desktop computers

today that do not already have an on

board network on their motherboard.

The second picture is another example of a network card,

a PC Card SMC EZ Card 10/100 wireless network card.

These cards are used in laptop computers that do not

have a built-in wireless network.

Types of Network Interface Cards

Architecture Dependence

Network Adapters are architecture specific. In other words, if we are connecting to an Ethernet network we need to have an Ethernet NIC. They're also transmission medium specific. For example, when using Ethernet we can use either copper cabling or fiber optic. We need to choose the right Networking Adapter that matches the transmission medium and network architecture we are connecting to. For some older computers we use NICs that plug in to the system's expansion slots or which are external to the computer and connect through an existing computer port. Today, most computers come with built-in Network Adapters, and the most popular one is Ethernet NIC.

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Transceiver

The Network Adapter is responsible for taking the zeroes and ones and converting them into a signal which can be sent on the transmission medium. On an Ethernet network, a Network Adapter has what's called a Transceiver. The Transceiver is responsible for taking the digital data, which is represented by a series of zeroes and ones, and converting that to an electrical, radio or a

light signal. For example, a 0 might be represented as a zero voltage on the wire. A 1 might be represented by a positive voltage. The method that's used to represent zeroes and ones is often called the encoding scheme, which will depend on what kind of network architecture we're using or which type of Transceiver is necessary for the transmission medium. Different Transceivers can sends light signals or electrical signals on a wire, and for wireless NICs can send radio signals. To receive signals, the Transceiver converts digital signals from the network to digital data for the PC. Time markers identify when each bit should occur.

Older Network Adapters used to have an external Transceiver. External Transceiver is just an adapter that took digital signals from an AUI port on one end and translated those into an electrical signal using RJ45 or some other port. When we ordered a network card we had to order the right transceiver that connected to the card. Network Adapters today usually have the built-in Transceiver based on the media type that we need.

SFP Module

One form of a Transceiver that is gaining in use is an SFP module. SFP stands for Small Form Factor Pluggable. SFPs are typically used on Switches and Routers to easily modify the media type used by a port. Instead of having a port with a fixed media type, the port accepts the SFP module. To change the media type simply plugs in a different SFP module. For example, we can get an SFP to support copper or different specifications of fiber optic.

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GBIC

Another term we might hear is a GBIC. A GBIC is slightly larger than an SFP but performs the same function. A GBIC (GigaBit Interface Converter) is a larger-sized Transceiver that fits in a port slot and is used for gigabit media including copper and fiber optic. The SFP Transceiver is sometimes called a mini GBIC because it is smaller than the GBIC module. We should also mention an XFP transceiver, which is similar in size to an SFP but is used for 10 Gigabit networking.

Modem

Another type of Network Adapter is a Modem. Modem takes the digital zeroes and ones and converts it to an analog sound signal that can be carried across the telephone wires. Modem is actually an abbreviated term that means modulator/demodulator. Modulation is happening on the sending end where binary data is converted to analog waves, and Demodulation is happening on the receiving end where the analog waves are converted back to binary data. Again, there's an encoding scheme that identifies when the signal represents a 0 or a 1, and the Network Adapter must match both the architecture and the transmission medium that is used.

Media Converter

In some cases we may need to convert from one media type to another. For example, let's say that you had an Ethernet network that uses copper cabling but we had a server that had a fiber optic Network Adapter card. In this case we could use a fiber optic to Ethernet copper cable Media Converter. It's important to remember that media converters work within the same network architecture. For instance, the Media Converter can convert from one type of Ethernet to another that uses a different transmission cable, but it is not used to convert from something such as Ethernet to a different networking standard, for example a WAN standard such as ATM (we use a Bridge or a Router to do this). Converting from one architecture to another would require modifying the Frame contents to modify the Data Link layer address. Media Converters operate at the Physical layer, since they simply transform the signal from

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one encoding scheme to another. Media Converters don't read or modify the MAC address in any way.

Remember

Network Adapters are architecture and transmission medium specific. The Transceiver is responsible for taking the digital data, which is represented by a series of zero’s and ones, and converting that to an electrical, radio or a light signal. The method that's used to represent zero’s and ones is called the Encoding Scheme. Modem takes the digital zero’s and ones and converts it to an analog sound signal that can be carried across the telephone wires. Media Converters operate at the Physical layer, since they simply transform the signal from one encoding scheme to another.

Network Interface Card (NIC) or simply Network Adapter, connects a host to the network medium. NIC is responsible for transmitting frames on the networking medium, that is, for converting binary data into a specific format to be sent on the network medium.

The Role of the Network Interface Card

Network interface cards, usually referred to as NICs, act as the physical interface or

connection between the computer and the network cable. Figure 2.24 shows a NIC with

a coaxial-cable connection. The cards are installed in an expansion slot in each

computer and server on the network.

After the NIC has been installed, the network cable is attached to the card's port to make the actual physical connection between the computer and the rest of the network.

Run the c02dem01 and c02dem02 videos located in the Demos folder on the CD accompanying this book to view a demonstration of how to install a network interface card (NIC).

Figure 2.24 A sample NIC

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The role of the NIC is to:

Prepare data from the computer for the network cable.

Send the data to another computer.

Control the flow of data between the computer and the cabling system.

Receive incoming data from the cable and translate it into bytes that can be understood by the computer's central processing unit (CPU).

Stated at a more technical level, the NIC contains the hardware and firmware (software

routines stored in read-only memory, ROM) programming that implements the Logical

Link Control and Media Access Control functions in the data-link layer of the OSI

reference model.

Preparing the Data

Before data can be sent over the network, the NIC must change it from a form the

computer can understand to a form that can travel over a network cable.

Data moves through a computer along paths called buses. These are actually several

data paths placed side by side. Because the paths are side by side (parallel), data can

move along them in lateral groups instead of in a single (serial) data stream.

Older buses, such as those used in the original IBM personal computer, were known as

8-bit buses because they could move data 8 bits at a time. The IBM PC/AT computer

used a 16-bit bus, which means it could move data 16 bits at a time. Computers

manufactured today use 32-bit buses. When data travels on a computer's bus, it is said

to be traveling in parallel because the 32 bits are moving along side by side. Think of a

32-bit bus as a 32-lane highway with 32 cars moving side by side (moving in parallel),

each carrying one bit of data.

On the network cable, however, data must travel in a single stream of bits. When data

travels on a network cable it is said to be traveling as a serial transmission because one

bit follows another. In other words, the cable is a one-lane highway, and the data always

travels in one direction. The computer is either sending or receiving data, but never both

at the same time.

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The NIC takes data that is traveling in parallel as a group and restructures it so that it

will flow through the 1-bit-serial path of the network cable. Figure 2.25 shows a server

converting parallel data to serial data on the network. This is accomplished through the

translation of the computer's digital signals into electrical or optical signals that can

travel on the network's cables. The component responsible for this is the transceiver

(transmitter/receiver).

Figure 2.25 Parallel data stream converted to a serial data stream

Network Address

In addition to transforming data, the NIC also has to advertise its own location, or address, to the rest of the network to distinguish it from all the other cards on the network.

A committee of the Institute of Electrical and Electronics Engineers (IEEE) assigns blocks of addresses to each NIC manufacturer. The manufacturers hardwire these addresses into chips on the card by a process known as "burning" the address into the

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card. With this process, each NIC—and therefore each computer—has a unique address on a network.

The NIC also participates in several other functions in sequence as it takes data from the computer and gets it ready for the network cable:

1. The computer and NIC must communicate in order to move data from the computer to the card. On cards that can utilize direct memory access (DMA, defined later in this lesson), the computer assigns some of its memory space to the NIC.

2. The NIC signals the computer, requesting the computer's data.

3. The computer's bus moves the data from the computer's memory to the NIC.

Because data can often move faster on the bus or the cable than the NIC can handle,

the data is sent to the card's buffer, a reserved portion of RAM. Here it is held

temporarily during both the transmission and reception of data.

Sending and Controlling Data

Before the sending NIC actually sends data over the network, it carries on an electronic

dialog with the receiving NIC so that both cards agree on the following:

The maximum size of the groups of data to be sent

The amount of data to be sent before confirmation of receipt is given

The time intervals between sending data chunks

The amount of time to wait before confirmation is sent

How much data each card can hold before it overflows

The speed of the data transmission

If a newer, faster, more sophisticated NIC needs to communicate with an older, slower

NIC, both need to find a common transmission speed that each can accommodate.

Some newer NICs incorporate circuitry that allows the faster card to adjust to the rate of

the slower card.

Each NIC signals to the other indicating its own parameters and accepting or adjusting to the other card's parameters. After all the communication details have been determined, the two cards begin to send and receive data.

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Configuration Options and Settings

Network interface cards often have configurable options that must be set in order for the

card to function properly. Some of the older designs use externally mounted dual inline

package (DIP) switches as shown in Figure 2.26. The following are examples of

configurable options:

Interrupt (IRQ)

Base input/output (I/O) port address

Base memory address

Transceiver

NOTE:

Settings on older NICs are made by means of software, jumpers, or a combination of

both; see the NIC product documentation for the appropriate software or jumper

settings. Many newer NICs use Plug and Play (PnP) technology; consequently, older

cards that require setting options manually are becoming obsolete. (Plug and Play is

discussed in more detail later in this lesson.)

Figure 2.26 Older NIC with DIP switches

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Interrupt Request (IRQ) Lines

Interrupt request lines (IRQs) are hardware lines over which devices such as I/O ports,

the keyboard, disk drives, and NICs can send interrupts or requests for service to the

computer's microprocessor.

Interrupt request lines are built into the computer's internal hardware and are assigned different levels of priority so that the microprocessor can determine the relative importance of incoming service requests.

When the NIC sends a request to the computer, it uses an interrupt—an electronic signal sent to the computer's CPU. Each device in the computer must use a different interrupt request line. The interrupt line is specified when the device is configured. For examples, see Table 2.5 that follows.

In most cases, IRQ3 or IRQ5 can be used for the NIC, as we will see later in this chapter. IRQ5 is the recommended setting if it is available, and it is the default for most systems. Use a system diagnostic tool to determine which IRQs are already being used.

If neither IRQ3 nor IRQ5 is available, refer to the following table for alternative values to use. The IRQs listed here as available usually can be used for a NIC. If the computer does not have the hardware device listed for a specific IRQ, that IRQ should be available for use.

Table 2.5 Standard IRQ Settings

IRQ Computer with an 80486 processor (or higher)

2(9) EGA/VGA (enhanced graphics adapter/video graphics adapter)

3 Available (unless used for second serial port [COM2, COM4] or bus mouse)

4 COM1, COM3

5 Available (unless used for second parallel port [LPT2] or sound card)

6 Floppy-disk controller

7 Parallel port (LPT1)

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8 Real-time clock

10 Available

11 Available

12 Mouse (PS/2)

13 Math coprocessor

14 Hard-disk controller

15 Available (unless used for secondary hard-disk controller)

Base I/O Port

The base I/O port specifies a channel through which information flows between the

computer's hardware (such as the NIC) and its CPU. The port appears to the CPU as

an address.

Each hardware device in a system must have a different base I/O port number. The port numbers, in hexadecimal format (the system that uses 16 rather than 10 as the basis for its numbering) in the following table, are usually available to assign to a NIC unless they are already in use. Those with a device listed next to them are addresses commonly used for the devices. Check the computer documentation to determine which addresses are already in use.

Table 2.6 Base I/O Port Settings

Port Device Port Device

200 to

20F

Game port 300 to

30F

NIC

210 to

21F

310 to

31F

NIC

220 to

22F

320 to

32F

Hard-disk controller (for PS/2 Model 30)

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230 to

23F

Bus

mouse

330 to

33F

240 to

24F

340 to

34F

250 to

25F

350 to

35F

260 to

26F

360 to

36F

270 to

27F

LPT3 370 to

37F

LPT2

280 to

28F

380 to

38F

290 to

29F

390 to

39F

2A0 to

2AF

3A0 to

3AF

2B0 to

2BF

3B0 to

3BF

LPT1

2C0 to

2CF

3C0 to

3CF

EGA/VGA

2D0 to

2DF

3D0 to

3DF

CGA/MCGA (also EGA/VGA, in color video

modes)

2E0 to

2EF

3E0 to

3EF

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2F0 to

2FF

COM2 3F0 to

3FF

Floppy-disk controller; COM1

Base Memory Address

The base memory address identifies a location in a computer's memory (RAM). The

NIC uses this location as a buffer area to store the incoming and outgoing data frames.

This setting is sometimes called the RAM start address.

NOTE

A data frame is a packet of information transmitted as a unit on a network. Often, the

base memory address for a NIC is D8000. (For some NICs, the final "0" is dropped from

the base memory address—for example, D8000 would become D800.) When

configuring a NIC, you must select a base memory address that is not already being

used by another device.

NOTE

NICs that do not use system RAM do not have a setting for the base memory address.

Some NICs contain a setting that allows you to specify the amount of memory to be set

aside for storing data frames. For example, for some cards you can specify either 16 KB

or 32 KB of memory. Specifying more memory provides better network performance but

leaves less memory available for other uses.

Selecting the Transceiver

The NIC can have other settings

that need to be defined during

configuration. For example, some

cards come with one external and

one on-board transceiver. Figure

2.27 shows a NIC with both on-

board and external transceivers. In

this case, you would have to decide

which transceiver to use and then

make the appropriate choice on

your card.

Making the choice on the card is usually done with

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jumpers. Jumpers are small connectors that tie two pins together to determine which circuits the card will use.

NIC, Bus, and Cable Compatibility

To ensure compatibility between the computer and the network, the NIC must:

Fit with the computer's internal structure (data bus architecture).

Have the right type of cable connector for the cabling.

For example, a card that would work in an Apple computer communicating in a bus

network will not work in an IBM computer in a ring environment: The IBM ring requires

cards that are physically different from those used in a bus; and Apple uses a different

network communication method.

Data Bus Architecture

In the personal computer environment, there are four types of computer bus

architectures: ISA, EISA, Micro Channel, and PCI. Each type of bus is physically

different from the others. It is essential that the NIC and the bus match. Figure 2.28

shows examples of each type of computer bus.

Industry Standard Architecture (ISA)

ISA is the architecture used in the IBM PC, XT, and AT computers, as well as in all their clones. It allows various adapters to be added to the system by means of plug-in cards that are inserted in expansion slots. ISA was expanded from an 8-bit path to a 16-bit path in 1984 when IBM introduced the IBM PC/AT computer. ISA refers to the expansion slot itself (an 8-bit slot or a 16-bit slot). The 8-bit slots are shorter than the 16-bit slots that actually consist of two slots, one behind the other. An 8-bit card could fit into a 16-bit slot, but a 16-bit card could not fit into an 8-bit slot.

ISA was the standard personal-computer architecture until Compaq and several other companies developed the EISA bus.

Extended Industry Standard Architecture (EISA)

This is the bus standard introduced in 1988 by a consortium of nine computer-industry companies: AST Research, Compaq, Epson, Hewlett-Packard, NEC, Olivetti, Tandy, Wyse Technology, and Zenith.

EISA offers a 32-bit data path and maintains compatibility with ISA, while providing for additional features introduced by IBM in its Micro Channel Architecture bus.

Micro Channel Architecture

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IBM introduced this standard in 1988 at the time it released its PS/2 computer. Micro Channel Architecture is electrically and physically incompatible with the ISA bus. Unlike the ISA bus, the Micro Channel functions as either a 16-bit or a 32-bit bus and can be driven independently by multiple bus master processors.

Peripheral Component Interconnect (PCI)

This is a 32-bit local bus used in most Pentium computers and in the Apple Power Macintosh computers. The current PCI bus architecture meets most of the requirements for providing Plug and Play functionality. Plug and Play is both a design philosophy and a set of personal computer architecture specifications. The goal of Plug and Play is to enable changes to be made to a personal-computer configuration without any intervention by the user.

Figure 2.28 ISA, EISA, Micro Channel, and PCI network interface cards

Network Cabling and Connectors

The network interface card performs three important functions in coordinating activities

between the computer and the cabling: it

Makes the physical connection to the cable.

Generates the electrical signals that travel over the cable.

Controls access to the cable by following specific rules.

To select the appropriate NIC for your network, you first need to determine the type of

cabling and cabling connectors it will have.

As discussed in the previous lesson, each type of cable has different physical characteristics that the NIC must accommodate. Each card is built to accept at least one type of cable. Coaxial, twisted-pair, and fiber-optic are the most common cable types.

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Some NICs have more than one interface connector. For example, it is not uncommon for a NIC to have a thinnet, thicknet, and twisted-pair connector.

If a card has more than one interface connector and does not have built-in interface detection, you should make a selection by setting jumpers on the card itself or by using a software-selectable option. Consult the NIC documentation for information on how to properly configure the card. Three examples of typical connectors found on NICs are shown in the following three illustrations.

A thinnet network connection uses a coaxial BNC connector as shown in Figure 2.29.

Figure 2.29 Thinnet network connections for a coaxial BNC connector

A thicknet network connection uses a 15-pin attachment unit interface (AUI) cable to connect the 15-pin (DB-15) connector on the back of the NIC to an external transceiver. As discussed earlier in Lesson 1, the external transceiver uses a vampire tap to connect to the thicknet cable. Figure 2.30 shows a 15-pin AUI connection.

Figure 2.30 thick net network connections for a 15-pin AUI

IMPORTANT

Be careful not to confuse a joystick port with an AUI external transceiver port; they look

alike, but some joystick pins carry 5 volts DC, which can be harmful to network

hardware as well as to the computer. You need to be familiar with the specific hardware

configuration in order to determine whether the connector is for a NIC or a joystick.

Similarly, be careful not to confuse 25-pin SCSI ports with parallel printer ports. Some

older SCSI devices communicated through the same kind of DB-25 connector as these

parallel ports, but neither device will function when plugged into the wrong connector.

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An unshielded twisted-pair connection uses a RJ-45 connector, as shown in Figure

2.31. The RJ-45 connector is similar to a RJ-11 telephone connector but is larger in size

and has eight conductors; a RJ-11 only has 4 conductors.

Figure 2.31 RJ-45 connector

Network Performance

Because of the effect it has on data transmission, the NIC has a significant effect on the

performance of the entire network. If the card is slow, data will not pass to and from the

network quickly. On a bus network, where no one can use the network until the cable is

clear, a slow card can increase wait times for all users.

After identifying the physical requirements of the NIC—the computer bus, the type of connector the card needs, and the type of network in which it will operate—it is necessary to consider several other factors that affect the capabilities of the card.

Although all NICs conform to certain minimum standards and specifications, some cards feature enhancements that greatly improve server, client, and overall network performance.

You can speed up the movement of data through the card by adding the following enhancements:

Direct memory access (DMA) With this method, the computer moves data directly from the NIC's buffer to the computer's memory, without using the computer's microprocessor.

Shared adapter memory In this method, the NIC contains RAM that it shares with the computer. The computer identifies this RAM as if it is actually installed in the computer.

Shared system memory In this system, the NIC's processor selects a section of the computer's memory and uses it to process data.

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Bus mastering With bus mastering, the NIC takes temporary control of the computer's bus, bypasses the computer's CPU, and moves data directly to the computer's system memory. This speeds up computer operations by freeing the computer's processor to deal with other tasks. Bus mastering cards can be expensive, but they can improve network performance by 20 to 70 percent. EISA, Micro Channel, and PCI network interface cards offer bus mastering.

RAM buffering Network traffic often travels too fast for most NICs to handle. RAM chips on the NIC serve as a buffer. When the card receives more data than it can process immediately, the RAM buffer holds some of the data until the NIC can process it. This speeds up the card's performance and helps keep the card from becoming a bottleneck.

On-board microprocessor With a microprocessor, the NIC does not need the computer to help process data. Most cards feature their own processors that speed network operations.

Servers

Because they handle such high volumes of network traffic, servers should be equipped

with the highest-performance cards possible.

Workstations

Workstations can use less expensive NICs if their main network activities are limited to

applications, such as word processing, that do not generate high volumes of network

traffic. Recall, though, that on a bus network, a slow NIC can increase wait times for all

users. Other applications, such as those of databases or engineering, will quickly

overwhelm inadequate NICs.

Specialized NICs

So far, this lesson has focused on standard network interface cards. In the majority of

situations, you will be using one of these cards to connect each computer to the

physical network. In reality, some situations will require the use of specialized network

connections and therefore require specialized network cards. The remainder of this

lesson introduces you to three varieties of these specialized cards.

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Wireless NICs

Some environments require an alternative to cabled computer networking. Wireless

NICs are available that support the major network operating systems. Wireless

networks are discussed in detail in the next lesson.

Wireless NICs often come with many features. These include:

Indoor omnidirectional antenna and antenna cable.

Network software to make the NIC work with a particular network.

Diagnostic software for troubleshooting.

Installation software.

These NICs can be used to create an all-wireless LAN or to add wireless stations to a

cabled LAN.

Usually, these NICs are used to communicate with a component called a wireless concentrator that acts as a transceiver to send and receive signals.

NOTE

A concentrator is a communications device that combines signals from multiple sources,

such as terminals on a network, into one or more signals before sending them to their

destination.

Fiber-Optic NICs

"Fiber to the desktop" has become a catchphrase for the computing industry. As

transmission speeds increase to accommodate the bandwidth-hungry applications and

multimedia data streams that are common on today's intranets, fiber-optic network

cards allow direct connections to high-speed fiber-optic networks. These cards have

recently become cost-competitive, and it's expected that their use will someday be

commonplace.

Remote-Boot PROMs

In some environments, security is such an important consideration that workstations do

not have individual floppy-disk drives. Without these, users are not able to copy

information to floppy or hard disks and, therefore, cannot take any data from the

worksite.

However, because computers normally start from either a floppy or a hard disk, there has to be another source for the software that initially starts (boots) the computer and

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connects it to a network. In these environments, the NIC can be equipped with a special chip called a remote-boot PROM (programmable read-only memory) that contains the hardwired code that starts the computer and connects the user to the network.

With remote-boot PROMs, diskless workstations can join the network when they start.

Network Interface Card

The circuit, which together with connectors and wiring, creates physical performance protocols and the OSI model is the interface between the computer and Circuit Embedded communication system, called the Network Interface Card - NIC. What network card quality makes its own processor that takes care of how to integrate a network of media and communication. If most of these fundamental tasks left to the microprocessor, allows the design of cheaper network cards, which is acceptable for computer users but not for the server. Program support, which takes account of the protocols, along with the card constitutes an interface between the computer and communications subnet.

IEEE (The Institute of Electrical and Electronics Engineering) has established a number of ways in which network cards transmit information through the media, mostly various types of lines, adopted by ISO and relate to a variety of computing platforms.

Standards are known under the designation 802.1 to 802.11 onwards that essentially define different topology and data transfer methods, in general:

802.1 Defines the relationship between the IEEE and ISO standards model.

802.2 MAC (Medium Access Control) sublayer and LLC (Logical Link Control) protocols; Standard of communication layer connection and connectivity. Describing the medium access control mechanism and logical data and their reception and transmission (transfer). Standards continue to describe the physical layers of the OSI model.

802.3 CSMA / CD (Carrier Sense Multiple Access / Collision Detection); Bus standards, protocols in which stations listen transmission medium that is what they are doing other stations and depending on the data sent or not, and the mechanism of availability of testing media networks, and if the medium is busy not accessed the network to avoid the collision, the most commonly used in ETHERNET.

802.4 Token Bus; Mechanism for transmitting packets from station to station in the sender has 'put' information and address (code) of the destination station and a destination that takes a package (sometimes called 'tokens') comes up to him

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and when the address is in the package agreed with the destination address. The order of transmitting stations is random.

802.5 Token Ring; Mechanism similar to the previous except that 'tokens' constant travels in a circle in the same direction. Use the type of ring topology.

802.6 DQDB (Distributed Queue Dual Bus); Standard that supports communication through light fibers, support networks of type MAN (Metropolitan Area Network) and WAN (Wide Area Network), and the city and state-transnational networks.

802.11 DSSC (Direct Sequence Spread Commission); Used CSMA / CA Technology (Carrier Sense Multiple Access / Collision Avoidance). Type and speed of communication can be recognized by standard which indicates the following suffix (a, b, g, n, ac). Standard that supports wireless communications developed several versions of the operating frequency of 2.4 GHz and 5 GHz at speeds of 1-150 Mbps (up to n standard) or up to 1.7 Gbps for four-channel standard (standard ac). This standard belong to Wi-Fi devices that work according to the specifications established for better interoperability which adheres to a couple of hundred companies (3Com, Cisco ...). Standard mechanism used positive confirmation of connection (ACK - explicit acknowledgment packet), which requires that you first examine the state of the media in order to determine its availability.

802.16 WiMAX (Worldwide Interoperability for Microwave Access); Wireless technology that enables wireless broadband access within the frequency range of 2-11 GHz. Providing broadband access without the need to create a direct line of sight, LOS - Line of Sight between the transmitting and receiving antenna. Within a radius of 8 km is provided to beneficiaries for the joint use of total throughput capacity of over 75 Mbps. Therefore, the available resources are divided into the number of users currently present within the geographical area of operation. By the way, the part of the working frequency ranges and microwave ovens that 'cooked dinner' :-). Defines two standards, one for the fixed wireless network and the other for the mobile network.

The card is to connect computers in the same network topology. Connect different network topologies can be done by inserting multiple cards for different configurations of the server each 'serving' their topological manifold. Of course, the network needs to support software supports a variety of network systems. NetWare network type system in its structure has implemented support for the server to perform the task of bridge and router and is diverse enough to insert the card.

PC network card is configured for one of the most common types of I / O bus (ISA, VLB or PCI) and usually supports ISA, PCI, or PCI-E bus, which fully meet the requirements concerning network communications. The network card on the front will have one or more types of connections:

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1.) THIN ETHERNET (thin coaxial cable) - bus topology with 'transceiver' (hand-transmitter) installed on the card. Coaxial cable via BNC-T by binding directly to the card; has greater immunity to noise, typical for bus topology. The solution is cheap, but does not tolerate poor grounding. Interruption or damage to the cable causes the complete dysfunction of the entire network 2.) TWISTED-PAIR (twisted four pairs of wires) - star topology with the hub (traffic center) and RJ45 PTT connector type for the phone. Can be shielded STP and UTP-unshielded, are cheaper and easier to install. Increasing popularity not only gets the relatively cheap connecting wiring but also due to the large fall in the price of active network equipment. Network reliability is significantly higher compared to the Bus topology. 3.) THICK ETHERNET (thick coaxial cable + TRANSCEIVER) - Device that connects to the network card using 'transceiver' cable (15-pin AUI connector). The solution is generally no longer used Looking for quality grounding. Interruption or damage to the cable causes the complete dysfunction of the entire network.Card that contains several types of connections commonly called combined (combo) network card.

Figure* 3.6.17 Bracket of 'Combo' PC network card / NIC Examples. ( +/- )

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Of course, it is not possible to simultaneously use multiple ways of connecting the network card to the network, but only one of them. In the configuration file card should define what kind of connection with the card to work. NIC when no appropriate connector for connecting portable media, the AUI (Attachment Unit Interface) connector that allows connection to a variety of media with appropriate transceiver's (converters). Transceiver is basically a receiver-transmitter, and can and do transform the signal into another one of nature (electrically in the optical and vice versa). As the receiver-transmitter default is to have two-way communication. In addition, the network card can be active at the same time (configured) in a single network, regardless of the protocol used.

Cards with multiple interfaces, as shown in the previous Figure, usually called 'combo'-combined. Function of transceiver with 10Base2 and 10Base-T does electronics incorporated on the printed board network card.

Particularity about this are:

4.) FIBER-OPTIC (fibers) - the cable has two or more optical fiber because fiber only supports one-way communication. Provide good security for resistance external electromagnetic influences and high speed transfer data, but they are very expensive. Network card of this type systems are used to store huge amounts of data. 5.) WIRELESS (based on the use of electromagnetic waves) - Everyday all prevalent types of communication that enables connection PC via PCI or PCMCIA network card. There are also versions of USB devices that serve as a wireless communication device or even contain converter for converting wireless communication in a wired communication. commonly used in notebook computers.

There is widespread use of RJ45 connections and star network architectures. Namely price drop HUB and SWITCH devices in fully displacing a thin Ethernet cable to the network configurations because of the unreliability of the bus network topology. Thick Ethernet cable is used only in the old systems if they are to function. Besides better HUB or SWITCH is able to identify which network interface card or cable are not correct and that port is automatically disconnected from the system. SWITCH has additional features, better described in the Chapter of Intranet.

Each network adapter hardware device is assigned a unique number (MAC address - Media Access Control) which is given command of the OS can be read as a hex notation, for example 08:00:20:7B:2B:36 (48 bits), if the computer involved and active on the network. Special international organization assigns a set number of manufacturers of network cards so that no two cards in the world with the same hardware number. In this way they avoid the 'differences' between the cards in the

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network traffic. Hexadecimal first 6 digits MAC address indicates the manufacturer, and the next 6 unique card number of manufacturers. As there is no legal obligation on the registration network cards sold this information is not helpful in detecting 'naughty' users. Since the paper uses the NIC MAC address belongs to the L2 layer of the OSI model, of course with the L1 layer circuits. Transceiver (receiver-transmitter) is one L1 devices layer because it works only with signals is not addresses.

NIC has the following functional parts:

Module of transmitting-receiving - In essence they are transmitting and receiving circuits of signals with data.

Module of encoding-decoding - Allows the insertion of the synchronization bit sequence in the data just before the transmission, in order to maintain synchronization in receiving and transmitting, and extract the data when it receives.

Medium Access Module (MAC) - The most important module generates a transmission destination address, control and CRC field of FRAME, while receiving treatment addresses of FRAME and its reception, and error detection and procedure in the event of a fault. The algorithm of the module allows for this purpose provides processor designed with the associated memory in which the registered MAC algorithm.

Buffer for FRAME - A cache in which it is entered FRAME before transmitting or kept just received FRAME. It measured from a few kB to MB.

Interconnection towards the bus (computer) - Presents circuits which will send data to the computer in the bus to him recognizable form or vice versa. Therefore, they are designed for ISA, EISA, MC and other types of buses. This means that the card for one type of computer can not be used in another.

NIC hardware settings are:

o Number of interrupt - When NIC receives data informs the CPU becomes the arrival information via a signal interrupts - IRQ. Upon receipt of the interruption signal stops the current CPU task, writing where it left off, examining where the wire interruption occurred, and the number of stops and starts interruption vector table corresponding service software routine that knows how to process the received packets and which passes control to the CPU. Selection is usually IRQ 5, it is rarely used by computers LPT2, or PnP (Plug and Play - Insert and Work) if the NIC, BIOS and OS support it.

o DMA or DMM (Direct Memory Mapping - Shared Memory) - NIC may use one of the DMA channels to transfer data from the buffer and the NIC in the computer memory or memory mapped buffers in the NIC memory area in the range of 640 kB-1 MB. Then you have to specify a starting address of the NIC buffer and its size.

o I / O port address - I / O address must be chosen that does not conflict with existing devices, such as 300H or will ask itself if the NIC, BIOS and OS type PnP (Plug and Play).

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By the speed of data transmission in computer DMM is the fastest, followed by the I / O port, and DMA. It is possible to use, and combinations thereof.

Each card that is inserted into the slot motherboard should be granted free IRQ number and address (e.g. IRQ=5, I / O address=300H) and bridging specify which type of connectors used, the presence of BOOT ROM for stations without OS disk and so forth. If the slot's computer input multiple cards each must be individually configured in various interruptions and address since it is essentially more devices. This simplifies the task of using a PnP card is a new generation who are in communion with the BIOS and OS of the new generation automatically all adjusted.

Most modern motherboards for computers have built UTP network card, and when it comes to portable computers (laptops) often have a modem port (RJ11), UTP port (RJ45), and wireless connectivity for CSMA / CA technology to Wi-Fi 802.11x standard for connections to approximately 100 m and BLUETOOTH technology (radio link at 2.4 GHz) for close links to 10 m. Over greater distances (WAN), over 10 km, is designed for WiMax wireless technology based on the 802.16 standard, which is not a substitute for Wi-Fi standard that the example uses the SOHO environment. So, types of network interface card are very different regards to its purpose, protocol and interface.

In relation to the block diagram shown in Figure 7.4.9, the wireless card has additional devices that perform the modulation and demodulation of high-frequency signal with a signal from digital receiver and transmitter of network card to encrypt the content with regard to its protection from reading and network access security mechanism.

Processor

A processor, or "microprocessor," is a small chip that resides in computers and other electronic devices. Its basic job is to receive input and provide the appropriate output. While this may seem like a simple task, modern processors can handle trillions of calculations per second.

The central processor of a computer is also known as the CPU, or "central processing unit." This processor handles all the basic system instructions, such as processing mouse and keyboard input and running applications. Most desktop computers contain a CPU developed by either Intel or AMD, both of which use the x86 processor architecture. Mobile devices, such as laptops and tablets may use Intel and AMD CPUs, but can also use specific mobile processors developed by companies like ARM or Apple.

Modern CPUs often include multiple processing cores, which work together to process instructions. While these "cores" are contained in one physical unit, they are actually individual processors. In fact, if you view your computer's performance with a system monitoring utility like Windows Task Manager (Windows) or Activity Monitor (Mac OS X), you will see separate graphs for each processor. Processors that include two cores are called dual-core processors, while those with four cores are called quad-

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core processors. Some high-end workstations contain multiple CPUs with multiple cores, allowing a single machine to have eight, twelve, or even more processing cores.

Besides the central processing unit, most desktop and laptop computers also include a GPU. This processor is specifically designed for rendering graphics that are output on a monitor. Desktop computers often have a video card that contains the GPU, while mobile devices usually contain a graphics chip that is integrated into the motherboard. By using separate processors for system and graphics processing, computers are able to handle graphic-intensive applications more efficiently.

INTEL PROCESSOR AND AMD PROCESSOR

Every PC has a Central Processing Unit (CPU) this acts as the brain of your system. It

connects to the Motherboard and works alongside the other components processing

many instructions at the same time between the different hardware and memory

systems.

Advancements in CPU technology now mean systems typically come with Dual Core,

Triple core or Quad Core processors (on one single chip) instead of the traditional one

core per chip. Now the total number of Cores can slot into a socket as before and a

single heat sink and fan can keep everything to the right temperature.

Intel and AMD are the two companies who dominate the PC Processor market. Both

have been around for decades and have become the main Chip suppliers for the home

and business markets.

Both companies have fierce rivalry and they file and counter file court cases against

each other all we care about is that they have near identical chip products on the market

at the same time as they compete for the fastest chip and share of the market.

The competing products are very close to each other and really only the techies

compare the benchmarks before choosing.

Intel Pentium Dual Core Processors

The Intel Pentium processors with Intel dual-core technology deliver great

desktop performance, low power enhancements, and multitasking for

everyday computing.

Intel i3 Processors (Ivy Bridge)

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Intel Core i3 dual core processors provide 4-way multitasking capability, runs

at fixed speed ideal for typical tasks and media playback but not games.

Intel i5 Processors

Intel i5 usually quad core but some dual processors deliver the next level of

productivity. Mostly the same as i3 but with Intel Turbo Boost Technology,

delivers extra speed when you need it. Like the i3 integrated graphics is

included but is only ideal for normal use not for gaming.

Intel i7 Processors

Intel i7 processors dual or quad core for the most demanding applications

with cache and faster clock speeds. Quad-core processors feature 8-way

threading, four cores will run faster, and more L3 cache, but will consume

more power. High-end use, video and gaming with dedicated video card.

AMD A4 - These A4 processors have 2 processor

cores and include a Radeon graphics chip. Aimed

for use with lower end systems.

AMD A6 - A6 processors dual core, includes turbo

function similar to Intels allows for the processor to

adapt to the task needed. Iintegrated graphics, on

par with Core i3 range.

AMD A8 - 4 processor cores is comparable to the

i3 and low i5, its graphic part is faster than Intels

version, can handle light gaming with ease.

AMD A10 - 4 processors these quad cores are

comparable with the Intel i5, and some i7s should benefit from better battery life.

ASeries processors use the FM2 socket so they will only fit in a Motherboard with FM2.

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2013 AMD Piledrivers are the latest version Piledriver then

FX-4, FX-6, FX-8 for either 4-8 cores, they use the AM3+

socket so can only be used in Motherboards with AM3+

Each series of processor usually has a couple of

generations per series where enhancements and tweaks are made, the main thing to

check and consider is that the type of processor is compatible with your motherboard

and fits your need and budget.

My personal view is there is little difference between using both makes and have run

many stable and fast systems using both makes. The AMD processors do tend to run

hotter than the Intel versions, but with a suitable fan this is easily kept under control.

I would decide depending on your budget, don't be afraid of using AMD, the AMD range

will mirror closely to Intels in speed and performance and for general use you can use

either to run general programs and movie playback with ease. Gaming or video needs

you will have a dedicated video card to

spread the load and likely a larger budget.

Intel products have in my experience

always been consistently more expensive,

typically £20 than the AMD equivalent.

Throughout my use and builds I find the

AMD nearly always more affordable, partly

as Intel's products higher price is

sometimes because they are available more in retail packaging rather than cheaper

OEM offerings, this depends on the supplier.

Don't get to hung-up on reviews, you can view a number of benchmarks comparing the

Intel and AMD equivalents head to head, sometimes AMD will be ahead sometimes

Intel will be out in front. But unless you are crunching specific tasks you will not notice

the odd fraction of a second or couple of seconds here and there.

If you are looking to upgrade just the CPU of your system, then you need to check what

type of socket your Motherboard uses and then check what the current speed cpu is

against the fastest speed version which can be use in your existing Motherboard.

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My advice would be to always look at the whole range of CPUs available as sometimes

a small bit extra can get you a significant jump in the speed and performance. Last time

I checked a processor with slightly lower clock speed but with two extra cores for just

£10 more!

Of course if you are buying a new or barebones systems then you should check both

Intel and AMD unless you have a major preference, don’t forget the compatible

motherboard and maybe a memory upgrade.

If you can research the type of processor you are buying you may be able to gauge if it

is soon to be replaced for a newer series, which could mean the price of your upgrade

would be lower as suppliers look to make room for newer stock.

If you are buying an older Processor series you may struggle to find compatible cpus,

most suppliers will have a couple of the older type, otherwise you may need to resort to

a used, b-grade or auction supplier.

VIDEO CARDS

A video card (also called a video adapter, display card, graphics card, graphics

board, display adapter, graphics adapter or frame buffer and sometimes preceded by

the word discrete or dedicated to emphasize the distinction between this implementation

and integrated graphics) is an expansion card which generates a feed of output images

to a display (such as a computer monitor). Within the industry, video cards are

sometimes called graphics add-in-boards, abbreviated as AIBs, with the word "graphics"

usually omitted.

Video memory

Type Memory clock rate (MHz) Bandwidth (GB/s)

DDR 166 – 950 1.2 – 3.04

DDR2 2000 – 3600 128 – 200

GDDR5 900 – 5700 80 – 230

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Definition

A video card connects to the motherboard of a computer system and generates output images to display. Video cards are also referred to as graphics cards. Video cards include a processing unit, memory, a cooling mechanism and connections to a display device.

Functions

For relatively low-end computer systems, the ability to create output images can be integrated into the motherboard or central processing unit (CPU). However, if you want to watch movies or play games on your computer (and who doesn't, at least once in a while), a dedicated video card greatly improves the quality of the graphics. For serious gamers, a high quality video card may just be the most important part of the computer system. For rendering 3D graphics in particular, a high quality video card is a must.

A video card is a printed circuit board (like a motherboard) and contains its own processing unit and memory. It is kind of like a computer in itself. This essentially takes the load off the motherboard's CPU and memory to process images. The processing unit on a video card is referred to as a graphics processing unit (GPU). This is very similar to a CPU but its design is optimized to work with images. The memory on a video card is very similar to the regular Random-Access Memory (RAM) on a motherboard. A video card connects to the motherboard of a computer system using a slot, typically an Accelerated Graphics Port (AGP) or a Peripheral Component Interconnect Express (PCIe) connection.

*Video card with the major components labeled*

High performance video cards generate a lot of heat. Video cards therefore need to employ heat sinks, which consist of metal strips to distribute the heat evenly and dissipate the heat to the surrounding air. A heat sink is often located right on top of the GPU. Sometimes a fan is added for additional cooling. The video card in the photograph below includes both a heat sink on top of the GPU (the metal stripes) as well as a large fan in a plastic casing.

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*Video card with heat sink and cooling fan*

5 Types of Video Cards

Video cards are essential computer peripherals used in various ways, such as playing high definition video and rendering objects when editing an image or a video file. A good video card allows you to have the ultimate gaming experience when playing your favourite computer games. There are various types of video cards available in the market nowadays, and it is necessary to differentiate each type so as to make the right decision when purchasing a video card. There are 3 major video card connection types, namely PCI, AGP and PCI-Express. PCI express is widely used and is becoming the standard connection type for most of the video cards emerging from the market today.

1. On board Video Card

On board video cards are standard video cards that come along with the motherboard of your computer. It is a low-end video card capable of displaying web pages and low-capacity games. On board video cards do not have a dedicated memory of its own; instead, it shares memory with your computer system. On board video cards are ideal for those who are using the computer for basic purposes only, such as word processing and web applications. This type of video card cannot be upgraded, and once you add another video card, your on board video card will be disabled automatically.

2. Value Video Card

A Value video card is one step better than on board video card. It is capable of displaying web applications and is an essential element for a faster word processing

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task and other simple computer functions. Unlike on board video cards, a value video card has its own dedicated memory. However, value video cards cannot support newer video games and high definition playback of HD videos.

3. Enthusiast Video Cards

Enthusiast video cards are the latest video cards in the market. It can support playback of high definition videos and is capable of playing the newest computer games that need high frame rates per second. Enthusiast video cards are also capable of rendering objects when video editing. It has its own dedicated memory of up to 2 gigabytes or more and dual processors and is ideal for high physics processing. Enthusiast video cards are the most expensive video cards for computers.

4. Mainstream Cards

Mainstream video cards are the predecessors of enthusiast video cards. When a video card is replaced in the market with a newer, faster and better video card, the previous video card is then categorized as a mainstream video card. Depending on the model of the mainstream video cards, it is also capable of all the functions of the enthusiast video cards. The only limitation, however, is that it is not capable of playing newer PC games, which requires better and faster video cards.

5. Multiple Video Cards

Multiple screen video cards are video cards capable of handling display of up to four or more computers. It is ideally used in computer functions that need multiple application displays, such as but not limited to, disaster management, FOREX update and traffic management.

INSTALLATION OF VIDEO CARD

How to Install Video Card?

Are your games not performing as well as they do for others? Do you see amazing

screenshots and think, "I wish my computer could do that?" Often, getting those kind of

results starts with the video card. Upgrading your video card can be a daunting task,

especially with so many options out there, but with a budget in mind and a screwdriver

in hand, you'll have a beefy new card installed before you know it. See Step 1 below to

learn how.

1. Open your case. In order to find your old card, identify your power supply, and install the new one, you'll need to open your computer's case. Most modern cases have thumbscrews on the back that allow you to easily remove the side panels, but you may need a Phillips-head screwdriver in order to remove the screws on older cases.

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You should disconnect the power cable and all peripherals before removing the side panels.

Remove the panel on the opposite side of the motherboard. If you look on the back of your computer you will see a panel on one side that contains a variety of ports, including USB, Ethernet, display ports and more. This is the motherboard I/O panel, and will help you see which side the motherboard is located on. You can lay your computer on this side and remove the opposite panel so that you can easily access the motherboard.

2. Ensure that your power supply is up to the task. Powerful video cards require a

power supply that can give them the juice they need. If you're running an old

power supply, or you have a lot of other components drawing power, your power

supply might not make the cut. If this is the case, consider upgrading your power

supply at the same time that you upgrade your video card.

There are a variety of sites online that help you calculate power requirements by analysing all of the hardware currently installed or that you're planning to install. Search for "power supply calculator" using your favorite search engine.

Your power supply will also need PCI-E connectors. This usually isn't an issue if your power supply is newer, but power supplies older than 10 years may not have the appropriate connectors.

Your power supply's maximum wattage should be printed on a sticker affixed to the power supply. You may need to remove the power supply to find it.

3. Ensure that your motherboard supports the card. Virtually all video cards are

PCI-E these days, so you will need to ensure that you have at least one of these

slots. They are typically located closest to the processor in the row of PCI slots. If

you don't have any PCI-E slots, you may need to install a new motherboard if you

want to upgrade your video card.

Refer to your motherboard's documentation to find the layout diagram. This will help you identify where the PCI-E slots are located.

Installing a new motherboard will require that you reinstall your operating system.

Note: Most laptops do not allow you to upgrade the video card.

Use a tape measure to note both the vertical and horizontal clearance that you have available. Nearly all cards will have their dimensions listed in their product descriptions, allowing you to ensure that it will fit before you purchase it.

4. Strike a balance between price and power. Video cards can get expensive. Obscenely expensive. At a certain point, the average user won't be gaining any benefits from the increased cost of higher-end cards. Examine the applications you intend to use your card with and find a card that gives you the best power and reliability for your buck.

The more expensive cards are typically geared towards video card over clockers and users who want to use dual- or quad-card configurations.

Be sure to read as many reviews as possible before deciding on a card. There are lots of resources online for finding the best performance for your budget.

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Sites such as Tom's Hardware will publish comparison charts ranking the current most popular cards in all price ranges, and customer reviews on sites such as Newegg can provide insight into the average person's experience with the card.

Check the system requirements for your favourite games. See what video card is recommended to get the best performance out of the games you love, and also keep in mind the needs of future games.

5. Find cards that are recommended for your interests. Different cards are best

suited for different applications, though most cards excel at being jack-of-all-

trades. below are some of the more popular cards as of 2014:

Nvidia GTX 670 - This is a good all-around card that can run most games at Ultra settings without breaking a sweat. it is highly recommended for graphic designers and photoshop as well. You can usually find these for around $400. The Radeon R9 290 is also a good pick for around the same price.

AMD Radeon HD 6670 - This is a low end card that can handle most games at Medium to High settings. You can snag this card for less than $70.

Nvidia GTX 780 Ti - This is one of the best high-end cards at the moment that can handle pretty much anything you throw at it. It has a price to match too - about $700.

If you are focused on graphic design, look for cards with more on board memory, such as 3 or 4 GB. These will be more expensive, but will increase your rendering and encoding speeds.

6. Look at the display capabilities of the card. As display technology improves, so

do the number of options available on video cards. Your new card may support

HDMI, DVI, Display Port, VGA, or any combination of those. Check what your

monitor uses to connect, and purchase your card accordingly.

For the best possible quality, you will want to connect via HDMI or Display

Port.

If you want top run multiple monitors, ensure that the video card can support

multiple monitors with quality ports. You don't want one monitor on HDMI and

the other on VGA, because the VGA monitor will be low resolution and look

terrible next to the HDMI one.

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Part 2 of 3: Installing the Card

1. Uninstall your old drivers. One of the biggest potentials for errors and problems

stems from driver incompatibility. Before installing your new card, it is highly

recommended that you uninstall the drivers that Windows is currently using to

display graphics.

The quickest way to uninstall your drivers is to open the Device Manager and

uninstall from there. To open the Device Manager, search for it in the Start

menu or press ⌘ Win + X and select it from the menu (Windows 8 only).

Once in the Device Manager, expand the Display Adapters section. Right

click on your current display adapter and click Uninstall. Follow the prompts to

remove the driver from your computer. Your display will likely revert to low

quality, with large icons and blurry text. Power down your computer after

uninstalling the drivers.

2. Ground yourself. Whenever working with sensitive computer components, you

should always ensure that you are properly grounded. Electrostatic discharge

can damage or destroy your components, rendering them useless. Preferably

you will be using an anti-static wrist strap attached to exposed metal in your

case. If you don't have one, you can ground yourself by touching a metal water

tap.

Make sure that the open computer is not resting on carpet, and that you are

standing on tile or linoleum when working inside the computer.

Make sure that the computer is unplugged from the wall before you begin

working on the insides.

3. Identify the old card. You can find your old graphics card inserted into the PCI-E

or AGP slot on your motherboard (AGP cards are typically found on older

computers). Most video cards are fairly large, and will likely be the largest card

installed in your system. They often have fans and heat sinks attached to them.

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If your computer was using integrated graphics before (your monitor was

connected directly to the motherboard), then there will be no card to remove.

4. Remove your existing card. If you are upgrading video cards, you will want to

remove the old card before installing the new one. Unscrew the screw that is

connecting the card to the chassis. Most newer cards have a tab underneath

near the back of the PCI slot that will need to be released in order to pull the card

out.

When removing the card, pull it straight up so that you don't damage the PCI

slot.

Make sure to disconnect any displayed plugged into the old card before

removing it.

5. Clean out any dust. With the old card out, this would be a great time to clean out

some of the dust that's accumulated. Use a small vacuum or compressed air to

clear the dust from the crevices around the PCI slot. Dust can build up and cause

your components to overheat, so staying on top of cleaning will help your

computer run for a long time.

6. Insert the new card. Gently remove the card from its antistatic bag, avoiding

touching any of the contacts or circuitry. Insert it straight into the empty PCI-e slot

and apply even pressure to the top until it is fully seated. If you have a clip for

your PCI-E slot, you will hear it click into place.

You may need to remove the neighbouring panel if your video card is two

panels wide.

Make sure no cables or any other components are in the way before

completely seating the card.

7. Secure the card. Use case screws to secure the video card to the chassis. If the

video card is two panels wide, you will want to secure it with two screws, one for

each bay. Make sure the card is inserted completely before securing the screws.

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8. Connect the power supply. Most modern cards will have power supply connector

ports built-in to the top of back of the card. You will need to connect one or two

PCI-E connectors from the power supply, which are typically 6-pin cables.

Without connecting the power supply, these cards will not work properly.

Many video cards come packaged with adapters that will change your existing

connectors into ones that will fir into the video card.

9. Close up your computer. After you've verified that the card has been seated

properly, secured, and been connected to the power supply, you can close up

the case. Make sure to connect your display to the new video card. If you were

using on board video before, the monitor was likely plugged into the

motherboard. In order to take advantage of your new card, your display will need

to be connected to it.

For best results, use HDMI or Display Port to connect your display to your

video card. If your monitor or card does not support HDMI or Display Port, the

next best choice is DVI, followed by VGA.

Part 3 of 3: Installing Drivers and testing it out

1. Power on your computer. Your operating system will most likely detect the new

card and attempt to adjust your display so that it is using the optimal resolution

and color depth. Accept the changes and enter the operating system.

If your monitor does not display any picture at all, you need to troubleshoot your installation. Check to make sure you have the card properly installed and connected.

An irregular, jagged-looking or distorted picture might indicate a problem with your video card. Check that your card is properly installed before contacting the manufacturer.

2. Insert your driver disc or download the drivers. If your video card came with a

driver disc, you can insert it now to begin the driver setup process. If your card

did not come with a disk, or you want to ensure that you have the latest release

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of the drivers possible, you can download the drivers directly from Nvidia or AMD

(depending on what card you have).

3. Install the drivers. The driver installation process is mostly automatic, though you

may get asked if you want to install any additional video card management

software. This additional software is optional, but can help ensure that your

drivers stay up to date. Your display will most likely flicker and reset during the

installation process.

Drivers contained on a disc are almost always out of date by the time they are purchased, so you will most likely be asked to update after installing them.

4. Start up a game. Let's be honest: the reason you got this card is so that you can

play the latest and greatest games. So what better way to test it out than to fire

one up? Before starting to play, explore the game's Video settings menu. Turn all

of the settings up as high as they can go and give the game a whirl. If it performs

smoothly then you're good to go!

When setting the resolution, you should always try to keep it at your monitor's resolution. For most flat screen monitors, this is 1920x1080, though newer monitors have a higher native resolution than that.

If the game is choppy or otherwise performing badly, start lowering settings one-by-one. Don't worry too much if your card can't handle the Ultra settings; sometimes games come out that don't work right with any card!

A game's performance is affected by more than just the video card. Your processor, RAM, and even hard disk speed will all play a part in how the game performs.

Tips

As with anything you do inside a computer case, move slowly and carefully.

For maximum precision — like when you're pulling out your video card —

keep your arms close to your body and arrange your task so your arms move

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laterally across the front of your body. This will allow you to use your chest

and abdominal muscles as well as your arms to make fine adjustments.

Be aware that changing your computer video card may void your warranty.

For most computers, especially ones that you build yourself, this will not be

the case. You may not even be able to change the video card in other

computers you use, like your computer at work or at school.

POWER SUPPLY

A power supply unit (PSU) converts mains AC to low-voltage regulated DC power for the internal components of a computer. Modern personal computers universally use a switched-mode power supply. Some power supplies have a manual selector for input voltage, while others automatically adapt to the supply voltage.

Most modern desktop personal computer power supplies conform to the ATX specification, which includes form factor and voltage tolerances. While an ATX power supply is connected to the mains supply, it always provides a 5 V standby (5VSB) voltage so that the standby functions on the

computer and certain peripherals are powered. ATX power supplies are turned on and off by a signal from the motherboard. They also provide a signal to the motherboard to indicate when the DC voltages are in spec, so that the computer is able to safely power up and boot. The most recent ATX PSU standard is version 2.31 of mid-2008.

Functions

The desktop computer power

supply changes alternating

current from a wall socket to

low-voltage direct current to

operate the processor and

peripheral devices. Several

direct-current voltages are

required, and they must be

regulated with some

accuracy to provide stable operation of the computer. A power supply railor voltage

rail refers to a single voltage provided by a power supply unit (PSU). Although the term

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is generally used in electronic engineering, many people, especially computer

enthusiasts, encounter it in the context of personal computer power supplies.

First-generation microcomputer and home computer power supply units used a heavy

step-down transformer and a linear power supply. Modern computers use switched-

mode power supplies (SMPS) with a ferrite-cored high frequency transformer. The

switched-mode supply is much lighter and less costly, and is more efficient, than an

equivalent linear power supply.

Computer power supplies may have short circuit protection; overpower (overload)

protection, overvoltage protection, under voltage protection, overcurrent protection, and

over temperature protection.

Recent power supplies have a standby voltage available, to allow most of the computer

system to be powered off. When the computer is powered down but the power supply is

still on, it can be started remotely via Wake-on-LAN and Wake-on-ring or locally via

Keyboard Power ON (KBPO) if the motherboard supports it.

Power supplies may have passive or active power factor correction (PFC). Passive PFC

is a simple way of increasing the power factor by putting a coil in series with the primary

filter capacitors. Active PFC is more complex and can achieve higher PF, up to 99%.

Power Supply Unit - The power supply unit is the piece of hardware that's used to convert the power provided from the outlet into usable power for the many parts inside the computer case.

Important Power Supply Unit Facts

Motherboards, cases and power supplies all come in different sizes called form factors. All three must be compatible to work properly together.

A PSU is not usually user serviceable. For your safety, it's usually wise to never open a power supply unit.

Power Supply Unit Description

The power supply unit is mounted just inside the back of the case.

The side of the PSU facing outside the case has a male, three pronged port that a power cable, connected to a power source, plugs into. There is also often a power switch and a power supply voltage switch.

Two Types of Current

Alternating Current (AC)

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o Electrical current flows in both directions; positive and negative terminals continuously trade places (polarity)

Example: Electricity provided by Ameren UE Frequency at which AC electricity alternates is measured in cycles

per second, or hertz (Hz)

Direct Current (DC) o Electrical current flows in one direction; negative to positive

Example: Electricity provided by batteries

Type of Power

• PCs use DC voltage but power companies supply AC voltage. • The power supply in a computer converts high-voltage AC power to low-voltage

DC power. Safety Ground Wire

• Safety Ground Wire prevents electrons from energizing metal parts of the computer.

• Without grounding, severe shock and fires can occur.

• Safety grounds are connected to the exposed metal parts of the computer’s chassis.

• Do not use ungrounded plugs in PCs. AC POWER

• In the U.S. 115 V and 60 Hz – PCs may have a small switch on the back to choose

• 115 or 230 V (used in other countries) • Hot and neutral provide the path for AC • Four wires to the fuse box:

– Bare wire that goes to ground and not the pole – Two 115-volt hot wires (black) from the pole to the

• fuse box – Neutral wire from the pole (black or striped)

• House gets 230 V AC from the pole Testing AC Voltage

• Test all of the wall outlets that the PC uses – Include any peripheral devices plugged into a wall

outlet – Include the PC and the monitor plugs – Circuit testers are available – The ‘hot’ should output approximately 115 V, the

‘neutral’ should output approximately 0 V, and the

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‘ground’ should connect to ground (also approximately 0 V) DC Power

• DC power comes out of the computer’s power supply, and provides electricity to all the components in the PC

– Flows in one direction, from negative to positive – All PC power supplies provide both positive and negative voltages.

The Power Supply

• The power supply acts as a step-down transformer converting high voltage AC into 5, 12, and 3.3 V DC

– PCs use a 12V current to power motors on devices such as the hard drives, and CD-ROM drives

– PCs use a 5-volt/3.3-volt current to support on board electronics

The Power Supply

• AT and ATX are the two types of power supplies that can be installed in any PC • The ATX form factor motherboard, with its unique ATX power supply, dominates

today’s systems • All power supplies share a number of common features such as the power

connection, motherboard power, power switch, peripheral connections, and the fan.

Power Connections • The power supply connects to the power cord

through a standard IEC-320 connector • Each power supply must have standard AC

power from the company

AT Power Connectors

• P8 and P9 are a pair of connectors that link the AT power supply to the AT motherboard

• As they are ‘faced’, they cannot be installed backwards

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ATX Power Connector

• Uses a single P1 power connector • The P1 has a notched connector to ensure proper installation

ATX POWER CONNECTOR

POWER SUPPLY TEST • The computer must be turned on • Do not touch any chips or circuit boards to prevent damage • Do not touch a probe to the hot circuit and to ground at the same time! • Do not allow both probes to touch each other while one is touching hot and one is touching ground • Make sure a probe only touches one metal object or pin at a time! Power Supply Notes

• If you don’t detect any power – Disconnect all devices except the motherboard – check for power to the

motherboard by itself • If the motherboard gets power

– One of the devices is causing the problem • If the motherboard still does not have power

– Check the power coming from the power supply without the motherboard plugged in – if you get power then the motherboard has an issue

• Most PCs today come with a 230-watt or higher power supply – If you add too many devices the power supply may stop working due to

too much wattage being required Troubleshooting Power

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Diagnosing a Dead Power Supply

A failure of the internal electronics of the power supply can cause some of the most difficult to diagnose problems.

The secret to discovering that a power supply is dying lies in one word: Intermittent

A voltmeter can be used to verify if the power supply is working or not.

A failed power supply should be replaced rather than attempting to repair it.

Power supplies break more often than many other parts in a PC. CONNECTOR

It is the part of a cable that plugs into a port or interface to connect one device to another. Most connectors are either male (containing one or more exposed pins) or female (containing holes in which the male connector can be inserted).

Connector Types / Images

Male and Female connectors, do you really know the difference?

For SCSI connectors, see here.

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Monitor Connectors

HD15 15 pins in three rows, pins are skinnier than

a usual "DB" connector, thus it's got an "H" for

High Density. Used for PC's SVGA video cards

and monitor cables.

DB15 15 pins in two rows, pins

are just like a DB9 or DB25.

Used for Mac monitors.

BNC connectors are used on Macs, Sun's and just about

anything that's old and good.

DB9 9 pins in two rows, used on older monitors,

and VGA's. PS/2 style Serial ports also use DB9

connectors.

13W3 a bunch of "DB" style pins

and three funny looking coax

contacts. Used on Sun and Mac

monitors.

Other PC/Mac connectors

Parallel/Printer

CN36 (female) This is the connector

you see on the back of most printers.

CN36 (male) This is the connector used by

most printer cables.

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DB25 (female) This connector is used

for parallel printer output on the PC. It

is also used for SCSI output, especially

on the Mac.

DB25 (male) This is used for parallel

printers (and other parallel port devices) as

well as SCSI and serial ports. If you see a

male on the back of your computer, it is

usually your COM2 serial port.

HPCN36 male This is the new "Type-

C" IEEE-1284 Parallel port connector

which is used on some new laser

printers.

MINIDIN-8 (female) Serial Mac connector.

Mac Printers, Mac printer and modem

outputs, etc.

Serial

DB25 serial connector. On a computer,

this would be a male not a female as

pictured above.

DB9 serial connectors. On the computer

there should be a "male" connector, the

mouse or other serial device (modem,

digital camera) would have a female.

USB and Firewire connectors

"i.Link" connector. This is basically a 4-

pin Firewire/i.link/IEEE-1394

"Firewire" connector.This is a 6-pin

Firewire/IEEE-1394 connector.

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connector.

USB type "A" connector. Connects to

computer or USB Hub.

USB type "B" connector. Connects to

peripheral or to USB Hub.

Mini USB connector used on many

new USB digital cameras.

Mini USB 2.0 connector used on many new

USB digital cameras.

Other connectors

S-Video connector, sometimes called

S-VHS or Y/C video. There're 4 little

pins in there, it's called a DIN4.

RCA (above) connector. Standard stereo

connector.

3.5 mm Mini Phone Plug connector, (below)

used on computer sound cards.

SC connector, fiber optic network

connector.

ST connector, fiber optic network

connector.

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MTRJ fiber optic network connector.

To slink connector. Used for digital audio.

TROUBLESHOOTING MOTHERBOARD

The motherboard is the computer, so the usual symptom of a failed motherboard is a

completely dead system. Fans, drives, and other peripherals may spin up if the

motherboard is dead, but more often nothing at all happens when you turn on the

power. No beeps, no lights, no fans, nothing.

If you think you have a dead motherboard, think again. The most likely cause of a dead

system is a blown fuse or breaker at the wall receptacle. If you're certain the system is

getting power and you have just installed the motherboard, it's much more likely that

you've neglected to connect a cable or made some other basic error than that the

motherboard itself is bad, assuming of course that the problem motherboard is a high

quality product.

When Bad Motherboards Turn Good

Many online vendors have stopped accepting returns of "bad" motherboards for just this

reason. As it turns out, about 19 of 20 motherboards returned as defective are perfectly

good. The buyer simply didn't install the motherboard correctly. Even so, many

upgraders choose to buy their motherboards from a big-box store or other local source,

because of their generally better return policies. In fact, some people troubleshoot their

systems by buying a motherboard locally and then returning it if the motherboard turns

out not to be the problem. We think that's unethical, but as any vendor will tell you, it's

common practice.

What's in a Name?

Most name-brand motherboards, particularly those made by Intel and ASUS, are of very

high quality; cheap motherboards, including those used in most consumer-grade mass-

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market systems, are of very poor quality. We've used Intel and ASUS motherboards for

years. In a shipment of 100 motherboards, it's unusual to find even 1 DOA. In a

shipment of 100 cheap motherboards, it's not uncommon to find half or more DOA, and

many of the remainder failing soon after they're installed.

In a working system, it's very uncommon for a high-quality motherboard to fail other

than from lightning damage (see Computer Power Supplies and Protection) or other

severe abuse. In particular, it's nearly unheard of for a motherboard to fail while it is

running, as opposed to when you start the system. A dead system is more often caused

by a dead power supply than a dead motherboard, so the first step to troubleshoot an

apparently dead motherboard is to swap in a known-good power supply. If the system

remains completely dead with a known-good power supply, it's likely that the

motherboard is defective and must be replaced.

It's not uncommon for a motherboard to fail partially. For example, an ATA interface or

the embedded video, audio, or LAN may stop working, while the rest of the motherboard

functions appear to work normally. It's possible to work around such partial failures; for

example, by disabling the failed function in BIOS Setup and installing an expansion card

to replace the failed embedded function. We recommend against this practice, however,

because a partial motherboard failure is often soon followed by a complete failure.

Configuring CMOS

Each time a system boots, the BIOS boot screen appears momentarily. While this

screen is being displayed, pressing a designated key runs the CMOS Setup program,

which resides in firmware. CMOS Setup is used to configure BIOS and chipset settings

ranging from those as obvious as the Date and Time to those as obscure as memory

timings and bus settings.

BEAUTY IS ONLY SKIN DEEP

Some motherboards replace the standard BIOS boot screen with a logo splash screen.

Display the standard BIOS boot screen on such systems by pressing the Escape key

while the logo is visible.

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To invoke CMOS Setup, you normally press F1 (AMI), Del (Award), or F2 (Phoenix).

Other BIOS manufacturers use different keys, and some system and motherboard

manufacturers modify a standard BIOS to use another key. The key that invokes CMOS

Setup nearly always appears on the BIOS boot screen, but if your BIOS boot screen

isn't displayed or doesn't show that key, try Esc, Del, F1, F2, F10, Ctrl-Alt-S, or refer to

the documentation.

The exact appearance of CMOS Setup and the available options depend on the chipset,

the BIOS make and version, and changes made to the BIOS and CMOS Setup

programs by manufacturers. For example, two motherboards may use the same chipset

and BIOS, but one may give users complete freedom to configure chipset options, and

the other allows users access to only some of the settings and uses hard-wired values

for other settings.

All BIOSs default to a reasonable set of settings, one that allows the system to boot and

function normally. Beyond that, it's up to you to choose settings to configure the system

as you want it and to optimize its performance. Some BIOS settings are obvious things

like time and date, power management, boot sequence, and so on. Others, particularly

those segregated as advanced settings and chipset settings, are anything but obvious.

The brief help descriptions provided with them are usually not much help unless you

already understand the issue. The primary rule here is if you don't understand what a

setting is for, don't change it.

That's easy to say, but it ignores the fact that accepting default settings for obscure

options can result in a PC that performs significantly below its potential. PC and

motherboard manufacturers differ in how "aggressive" they are in choosing default

settings, particularly those for such things as memory timing. Those that tend toward

slower, more conservative default settings say, with some justification, that they cannot

predict what components particularly what speed and quality of memory a user will

install. Choosing conservative settings allows them to be sure that the motherboard will

at least work, if not optimally. Those who are more aggressive often PC makers who

control the specific memory and other components that are installed and who assume

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that users want the highest possible performance level and use components that

support those aggressive settings.

The first place to look for detailed CMOS Setup instructions is in the manual that came

with the computer or motherboard, or on the web page that supports that product. Some

manufacturers provide detailed explanations of general CMOS Setup and Chipset

Setup options, but many cover only basic BIOS settings and ignore chipset settings

entirely. If that's the case with your manual, the best sources of information about

advanced BIOS settings are Wim's BIOS (http://www.wimsbios.com) and Phil

Croucher's The BIOS Companion(http://www.electrocution.com/biosc.htm).

Updating the BIOS

When you upgrade a system without replacing the motherboard, the BIOS version it

uses can be a critical consideration. Some system features e.g., support for faster or

more recent processors, large hard disks, high-speed transfer modes, and AGP are

BIOS-dependent, so an in-place upgrade often requires a BIOS upgrade as well.

Fortunately, recent systems use a flash BIOS, which can be upgraded simply by

downloading a later version of the BIOS to replace the existing BIOS.

Don't Take Chances

Be extraordinarily careful when upgrading the system BIOS. Make absolutely sure that

the BIOS upgrade patch you apply is the exact one required for the current BIOS.

Applying the wrong BIOS update may make the motherboard unusable, short of

returning it to the factory for repair.

The exact method required to update the BIOS varies by motherboard manufacturer

and model. Some motherboards are updated simply by copying the updated BIOS file to

a floppy disk or CD and booting from it. Other motherboards use a DOS-based "flasher"

program that runs from floppy disk and installs the BIOS file when it executes. Intel

motherboards support Intel Express BIOS Update, which allows updating the BIOS from

within Windows simply by double-clicking an executable file. (Fortunately, Intel also

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provides floppy disk based BIOS update routines that those of us who run Linux or other

non-Windows operating systems can use to update our BIOSs.)

Although updating the BIOS is a pretty intimidating operation the first time you try it or

the tenth time, for that matter BIOS updates usually complete successfully if you do

everything by the numbers. But if you accidentally apply the wrong patch or if the

update process fails through no error of your own, the PC can end up non-bootable. If

this happens, there may not be an easy way to recover. Depending on the BIOS, one of

the following methods to recover from a failed BIOS update may be usable:

A few motherboards have dual BIOS chips. If you corrupt 1 BIOS during an update, you

can boot the system from the other BIOS and re-flash the corrupted BIOS.

Intel motherboards have a jumper that configures the motherboard for one of three

modes of operation: Normal, BIOS Update, and Recovery. To update the BIOS, you

must set that jumper to update mode. If the update fails for any reason, you can reset

the jumper to the Recovery position, which gives the motherboard just enough smarts to

access the floppy drive at boot time and attempt to load a BIOS update from the floppy

drive.

BELT AND SUSPENDERS

Because a failed BIOS update can have such dire results, never update a BIOS without

first connecting the system to a UPS, if only temporarily while doing the update. The

one time we violated that rule, sure enough, the lights flickered about five seconds after

we started the update. Hoping against hope that the PC hadn't crashed (this update was

one where the screen stays blank until the update is complete), we sat staring at the

blank screen for another half hour before we admitted to ourselves that we'd probably

just killed the motherboard. With our fingers crossed, we powered the system down and

back up again, but, as expected, it was deader than King Tut. Unless your luck is better

than ours, always use a UPS when flashing BIOS.

Symptoms and Diagnosis

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System has no power at all. Power light does not illuminate, fan inside the power supply

does not turn on, and indicator light on keyboard does not turn on.

PROBABLE CAUSE DIAGNOSIS SOLUTION

Power cable is unplugged.

Visually inspect power

cable.

Make sure power cable is

securely plugged in.

Defective power cable.

Visual inspection, try

another cable. Replace cable.

Power supply failure.

Power cable and wall socket

are OK, but system is still

dead. Contact technical support

Faulty wall outlet; circuit

breaker or fuse blown.

Plug device into socket

know to work and test.

Use different socket, repair

outlet, reset circuit breaker or

replace fuse.

System in-operative. Keyboard lights are on, power indicator lights are lit, and hard

drive is spinning.

PROBABLE CAUSE DIAGNOSIS SOLUTION

Expansion card is partially

dislodged from expansion

slot on the motherboard.

Turn off computer. Take

cover off system unit.

Check all expansion cards

to ensure they are securely

seated in slots.

Using even pressure on both

ends of the expansion card,

press down firmly on

expansion card.

Defective floppy disk drive

or tape drive.

Turn system off.

Disconnect the cables from

one of the floppy drives.

Turn on the system, check

Contact Technical Support.

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to see if the keyboard

operates normally. Repeat

until you have located

defective unit.

Defective expansion card. Turn computer off.

Remove an expansion card.

Make sure expansion card is

secure in expansion socket.

System does not boot from hard disk drive, can be booted from floppy disk drive.

PROBABLE CAUSE DIAGNOSIS SOLUTION

Connector between hard

drive and system board

unplugged.

When attempting to run the

FDISK utility described in

the HARD DISK section of

the manual you get a

message, INVALID DRIVE

SPECIFICATION.

Check cable running form

disk to disk controller on the

board. Make sure both ends

are securely plugged in;

check the drive type in the

Standard CMOS Setup (in

your motherboard manual).

Damaged Hard Disk or Disk

Controller.

Format hard disk; if unable

to do so, the hard disk may

be defective.

Contact Technical Support.

Hard Disk directory or FAT

is scrambled.

Run the FDISK program,

format the hard drive(See

HARD DRIVE section of

manual). Copy your backup

data back onto hard drive.

Backing up the hard drive is

extremely important. All Hard

Disks are capable of

breaking down at any time.

System only boots from Floppy Disk. Hard Disk can be read and applications can be

used, but booting from Hard Disk is impossible.

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PROBABLE CAUSE DIAGNOSIS SOLUTION

Hard Disk boot program has

been destroyed.

A number of causes could

be behind this.

Back up data and

applications files.

Reformat the Hard Drive as

described in the Hard Drive

section of the manual. Re-

install applications and data

using backup disks.

Error message reading "SECTOR NOT FOUND" or other error messages indication

certain data is not allowed to be retrieved.

PROBABLE CAUSE DIAGNOSIS SOLUTION

A number of causes could

be behind this.

Use a file by file backup

instead of an image backup

to backup the Hard Disk.

Back up any salvageable

data. Then do a low level

format, partition, and high

level format of the hard drive(

see Hard Disk section of your

manual for instructions). Re-

install all saved data when

completed.

Disk formatted on IBM PS/2 will not operate with this system.

PROBABLE CAUSE DIAGNOSIS SOLUTION

The IBM PS/2 uses a

different format than other

IBM PS/2 disk format will

not work in an AT type

Format disk in the AT type

computer insert disk into the

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computers. computer. IBM PS/2 and copy the files

you wish.

After install an expansion card (network card, tape drive card, etc.) the system no longer

works properly.

PROBABLE CAUSE DIAGNOSIS SOLUTION

No power to monitor.

All or part of the system may

be inoperable. The new card

may work but a mouse or

COM port may not work.

Change the interrupt or RAM

address on the new

expansion card. See the

documentation that came

with the new card in order to

change pin settings. many

expansion devices come with

proprietary software that will

assist you in doing this.

Screen message says "Invalid Configuration" or "CMOS Failure."

PROBABLE CAUSE DIAGNOSIS SOLUTION

Incorrect information

entered into the

configuration (setup)

program.

Check the configuration

program. Replace any

incorrect information.

Review system's equipment.

Make sure correct

information is in setup.

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Screen is blank.

PROBABLE CAUSE DIAGNOSIS SOLUTION

No power to monitor. Power connectors may be

loose or not plugged in.

Check the power connectors

to monitor and to system.

Make sure monitor is

connected to display card,

change I/O address on

network card if applicable.

Monitor not connected to

computer. See instructions above.

Network card I/O address

conflict. See instructions above.

System does not boot from hard disk drive, can be booted from floppy disk drive.

PROBABLE CAUSE DIAGNOSIS SOLUTION

Connector between hard

drive and system board

unplugged.

When attempting to run the

FDISK utility described in

the HARD DISK section of

the manual you get a

message, INVALID DRIVE

SPECIFICATION.

Check cable running form

disk to disk controller on the

board. Make sure both ends

are securely plugged in;

check the drive type in the

Standard CMOS Setup.

STORAGE DEVICES

What are Storage Devices?

Alternatively referred to as storage, storage media, or storage medium, a storage

device is any hardware device capable of holding information. There are two storage

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devices used in computers; a primary storage device

such as computer RAM and a secondary storage device

such as a computer hard drive. The secondary storage

could be a removable, internal, or external storage. The

picture shows an example of a Drobo, an external

secondary storage device.

Without a storage device, your computer would not be

able to save any settings or information and would be

considered a dumb terminal. Below, are some additional

examples of storage devices that are used with

computers.

HARD DISK DRIVE

Hard disk drive

A 2.5" SATA hard drive

Date invented 24 December 1954

Invented by IBM team led by Rey Johnson

A hard disk drive (HDD) is a data storage device used for storing and retrieving digital information using rapidly rotating disks (platters) coated with magnetic material. An HDD retains its data even when powered off. Data is read in a random-access manner, meaning individual blocks of data can be stored or retrieved in any order rather than sequentially. An HDD consists of one or more rigid ("hard") rapidly

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rotating disks (platters) with magnetic heads arranged on a moving actuator arm to read and write data to the surfaces.

Introduced by IBM in 1956, HDDs became the dominant secondary storage device for general purpose computers by the early 1960s. Continuously improved, HDDs have maintained this position into the modern era of servers and personal computers. More than 200 companies have produced HDD units, though most current units are manufactured by Seagate, Toshiba and Western Digital. Worldwide disk storage revenues were US $32 billion in 2013, down 3% from 2012.

The primary characteristics of an HDD are its capacity and performance. Capacity is specified in unit prefixes corresponding to powers of 1000: a 1-terabyte (TB) drive has a capacity of 1,000 gigabytes (GB; where 1 gigabyte = 1 billion bytes). Typically, some of an HDD's capacity is unavailable to the user because it is used by the file system and the computer operating system, and possibly inbuilt redundancy for error correction and recovery. Performance is specified by the time to move the heads to a file (Average Access Time) plus the time it takes for the file to move under its head (average latency, a function of the physical rotational speed in revolutions per minute) and the speed at which the file is transmitted (data rate).

The two most common form factors for modern HDDs are 3.5-inch in desktop computers and 2.5-inch in laptops. HDDs are connected to systems by standard interface cables such as SATA (Serial ATA), USB or SAS (Serial attached SCSI) cables.

As of 2014, the primary competing technology for secondary storage is flash memory in the form of solid-state drives (SSDs). HDDs are expected to remain the dominant medium for secondary storage due to predicted continuing advantages in recording capacity, price per unit of storage, write latency and product lifetime. However, SSDs are replacing HDDs where speed, power consumption and durability are more important considerations.

How to Install a Hard Drive

The hard drive is the primary storage location for all of your computer’s data. If you run

out of that storage, installing a new drive may be the most practical solution. If your

computer is dead, you may need to replace your old failed hard drive. In either case,

you can do it yourself instead of taking your computer into a repair shop. Read on after

the jump to learn how.

Method 1 of 2: Installing a Desktop Hard Drive

Power down the computer. Shut off the power supply

in the back. If you can access the inside where it

stands, you don’t need to unplug the computer.

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Otherwise, unplug the computer and place it somewhere that allows you to get inside.

Remove the case panels. You may need a Phillip’s

head screwdriver, but most newer computers have

thumbscrews. You will need to remove both sides

so that you can screw the hard drive in on both

sides.

Make sure you are grounded. If your computer is still

plugged in (but the power supply is switched off), you

can ground yourself by touching any metal part of the

case. Otherwise, make sure that you are grounded

before starting to work on the inside of the computer.

This will prevent electrostatic shock from damaging

the components of your computer.

Remove the old drive (if applicable). If you are removing an old hard drive, make sure all of the cables are disconnected from both the motherboard and the power supply. Unscrew all the screws on both sides of the hard

drive, and then slide it out of the housing.

You may need to remove more cables or cards

in order to access the hard drives in a tight

case.

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Insert your new drive. Remove it from the antistatic packaging and slide it into an open space in the hard drive housing. The drive should slide directly in, and the holes on the side of the drive should line up to the screw guides on the housing.

If you can, use a slot that has some space around it. This will improve airflow and

lead to a cooler system, but is not a critical concern.

Secure the hard drive. Once the hard drive has

been inserted, use the screws that came with it to

secure the hard drive in the housing. Ideally you

should use two screws on each side of the hard

drive. If the hard drive is loose, it can rattle and

cause more noise and lead to physical damage.

Tighten the screws to a firm tightness, but don’t over tighten as that may cause

damage as well.

Connect a SATA hard drive to the

motherboard. Newer hard drives will use SATA

cables, which are thin and resemble USB cables. Use

a SATA cable to connect the hard drive to the

motherboard. SATA cables can be connected in

either direction.

If you are connecting your primary hard drive, the SATA cable should be plugged

into the first SATA channel. This may be labelled SATA0 or SATA1. Refer to your

motherboard documentation for detailed information for your motherboard.

Secondary drives should be connected to the next available SATA channel.

Connect a PATA (IDE) hard drive to the

motherboard. IDE drives are older model hard drives

that can be identified by the long rows of pins on the

back. IDE Drives are connected via an IDE cable, which

is wide and flat. The cable is usually gray in color.

The blue end of the cable plugs into the

motherboard. The black connector plugs into your

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primary (Master) drive, while the black connector plugs into the secondary

(Slave) drive if applicable.

Set the jumper for your primary drive to Master. The jumper diagram should be

printed onto the hard drive. If you are installing a secondary drive but it is the only

drive connected to the cable, it should be set to Master as well.

Connect the power supply to the hard drive. Most

newer power supplies have SATA power

connectors, though older power supplies typically

only have Molex (4 pin) connectors. If this is the

case, and you are installing a SATA drive, you will

need a Molex-to-SATA adapter. IDE drives will use

the Molex connector.

Make sure that all of your connections are secure. Ensure that none of the cables

can come undone by wiggling them a little bit.

Close up your computer. Replace the case sides

and reconnect your cables if you had to move the

case to work on the inside. Turn the power supply

back on and then turn your computer on.

Finish the installation. Once you’ve got everything

connected and the computer turned back on, you’ll

need to finish the installation of the hard drive from

your computer. If you are replacing your primary

drive, you’ll have to reinstall your operating system.

If you are adding a new drive, you’ll need to format

the drive before you can use it.

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The Jumper Setting

SET THE JUMPER SETTING ON YOUR HARD DISK DRIVE

The hard disk drive will be detected as 32 GB, if the jumper is set to the 32 GB cli pin setting. The common jumper settings for Samsung Hard disk drives are listed below. Please check the label on your disk drive for the correct jumper setting.

IMPORTANT: Use the alternate jumper setting listed below under General Pin Setting. After changing the jumper, partition and format your Hard Disk Drive.

Configuring Hard Disk Drive (Master, Slave and Cable Select) - Setting the Jumper

If this is the only HDD in your computer, Set the pin setting to Master.

If this is the second HDD in your computer, set the pin setting to Slave.

If this is the second HDD in your computer, and the first drive is set to Cable Select, set the pin setting to Cable Select.

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If you are replacing the HDD in your computer, set the jumper setting to match that of the drive you are replacing.

Cable Select

This setting is the default setting for PATA/IDE Hard Disk Drives. With the cable select jumper settings, the BIOS determine whether a HDD is set as a Master or set as Slave by its position on the UDMA Cable.

If the HDD Jumper is set to the Cable Select and is connected to the black connector on the end of the UDMA cable, it is recognized as Set as Master for the PATA Controller.

If the HDD Jumper is set to the Cable Select and is connected to the black connector on grey connector on the Middle of the UDMA Cable, it is recognized as Set as Slave for PATA Controller.

NOTE: When using Cable Select, your system must meet the following conditions:

Your system Host Controller must support Cable Select.

Your Hard Drives must support Cable Select

Your cable must support Cable Select.

Set as Master:

Use this setting if you are installing additional Hard Disk Drive to a single UDMA Cable with a hard disk drive Set as Slave, jumper one hard disk drive to set as Master, and the other is to set as Slave.

Use this setting if you are installing additional HDD to a single UDMA cable and the Cable select setting is not recognized.

Set as Slave:

Use this setting if you are installing an additional HDD to a single UDMA Cable with a HDD Set as master, Jumper one HDD to Set as Master, and the other to set as Slave.

Use this setting if you are installing additional HDD to a single UDMA cable and the Cable select setting is not recognized.

32GB Clip Pin Setting

Use this on Computers manufactured before November 1998 when either you start up your computer and see the message, “Hard Disk Drive Controller Failure”, or your system stops responding during the booth process after installing a new drive. This occurs when the hard disk is too large for the BIOS to Support.

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How to Partition Your Hard Drive in Windows 7

Disk partitioning is to divide the hard drive into multiple logical units. People don’t often

choose to partition their hard disks, but it has many benefits. Mainly, by partitioning your

disk, you can separate your operating system from your data and thus reduce the

chances of your data becoming corrupted.

1. Open the Computer Management tool. Open the Start menu. Type “Computer

Management” in the search bar of the Start menu and press enter.

2. Select the Disk Management tool. Click on Disk Management on the left side of

the window and you should see all of the disks and their partitions on your

computer.

In the example in the picture, there is 1 disk with two partitions.

3. Make some space for the new partition. Right-click on the partition you wish to

re-size and select the Shrink Volume option.

In the example in the picture the (C:) drive is used.

Note: There may be a partition named System Reserved. It is not

recommended that you alter this partition at all.

4. Shrink the drive. Enter the size you wish to shrink your drive to in megabytes

(1000 MB = 1GB). Then click on the Shrink button.

In this example the drive is shrunk by 10000 MB or 10 GB.

Note: You cannot shrink your volume greater than the amount indicated in

theSize of available shrink space in MB section.

5. Create a new volume. You should now see a new unallocated partition in

yourDisk Management window. Right-click on the Unallocated partition and

select theNew Simple Volume option.

6. The New Simple Volume Wizard. The New Simple Volume Wizard should popup.

Click on the Next button to continue.

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7. Enter size of new partition. Enter the amount of memory you wish to allocate for

your new partition and click on the Next button.

In the example in the picture, the maximum memory available is allocated

to the new volume.

Note: You cannot make your new volume larger than the maximum

amount of memory available.

8. Give the new volume a letter name or path. Select from the menu, a letter name

for your new partition and click on the “Next” button.

The letter name chosen for the example in the picture is (E:)

The letter name or path is used by Windows to identify and navigate to

your new volume.

9. Settings for the new volume.

Click on the Format this volume with the following settings:

For File System, select NTFS

For Allocation unit size, select Default

For Volume Label, type the name you wish to give your new drive.

Click on the Perform a quick format

Then click on the Next button

10. Create the new volume. Look over your settings and click on the Finish button.

11. Format the new volume.

You will get a popup asking you to partition your new drive. Click on

the Format disk button.

A new window will popup. Keep the settings and click on the Start button.

A warning will popup. Click on the OK button.

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12. Check new volume. If everything was done correctly, you should now see your

new drive in the Disk Management window.

How to format a hard drive in Windows Vista, 7 or 8: get ready for a fresh install

How to quick format a hard drive

Windows Vista, 7 and 8 have a built-in Disk Management tool (see below), but the

fastest way to format a hard drive is to click the Start button, then Computer and right-

click on the hard drive you want to wipe (you can't format the drive on which Windows is

installed for obvious reasons). Choose Format… from the menu and a new window will

appear with a few formatting options.

By default Quick Format is checked, and you can choose the file system and allocation

unit size as well as changing the volume label (the drive's name). Typically, you can

leave all settings unchanged and click the Start button. In under a minute your hard

drive will be formatted.

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You should choose NTFS as the file system if it isn't already selected for Windows

Vista, 7 or 8.

Using Windows' built-in Disk Management tool

Type diskmgmt.msc into the search box in Vista or Windows 7 and then click on only

result that appears in the menu above, with the same name.

This is the easiest way to launch Disk Management, but you'll also find it in the Control

Panel if you search for 'disk' or look under the Administrative tools section, where it is

called 'Create and format hard disk partitions'.

Disk Management isn't as powerful as a standalone partition management tool, but it is

still useful. See also: Acronis True Image 2014 review

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When you install a new (additional) hard drive in your PC, you might wonder why it

doesn't appear in Windows Explorer. The reason is because it needs to be initialised

and formatted - you can do this in Disk Management.

When the tool loads, it will analyse all your computer's drives and will prompt you to

initialise a new disk that it finds.

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If your disk is larger than 2TB, you should opt for GPT (GUID Partition Table). This

setting also lets you create more than four partitions.

If you don't see a prompt, look in the list of drives and you should see one that says 'Not

Initialized'. Right-click on it and choose Initialize Disk.

Once that's done, right-click in the hatched Unallocated space and choose New Simple

Volume…

Follow the instructions, choosing how big you want the partition to be (in MB - 1024MB

= 1GB), and which drive letter you want (one will be chosen, but you can opt to change

it if you wish).

When you come to format the partition, our advice is the same as in the Quick Format

section above.

If you select a size for the partition that's smaller than the total capacity of the drive, say

500B on a 1TB drive, you'll end up with some unallocated space on the drive which you

can format by repeating the process you've just completed.

Changing a partition's size

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You can use Disk Management to expand or shrink a partition. Simply right-click on one

and choose the appropriate option from the menu that appears. If shrinking, the partition

will be checked to find out how much empty space it contains.

It's a little confusing as the numbers are displayed in MB rather than GB, but you can

adjust the amount of space to shrink and the 'Total size after shrink' will be updated.

You can't shrink a partition beyond the point where files are located - you may be able

to free up space by defragmenting the drive first.

Conversely you can only expand a partition if there is unused space on the drive. If not,

the option will be greyed out.

CD ROM DRIVE

What is CD ROM Drive?

CD-ROM drive is the place on a computer where a compact disc can be held, read and

played. An example of a CD-ROM drive is where a person can play a music CD on the

computer. CD-ROMs drive. A device for reading data from a CD-ROM.

Types of CD ROM Drives

CD-ROMs changed the way that information can be saved from a computer. In the past,

floppy discs were the media of choice, but they were quickly replaced because CD-

ROM's have a higher capacity of storage; they are faster and easier to store. Instead of

using multiple floppy discs to save one file, PC users can now store hundreds or even

thousands of data files on one CD-ROM.

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CD-ROM

CD-ROM stands for (Compact Disc Read Only Memory), and it is mainly used to mass produce audio CD's and computer games. Computer users can only read data and music from the discs, but they cannot burn their own information onto the discs, from their personal computers.

CD-R

CD-R also known as (Compact Disc Recordable) and WORM (Write Once Read Many) is a blank disc that users can put into a CD-ROM drive to burn or make a copy of their personal data, music, videos and information. CD-R's have to use special software to burn specific types of media or data. You cannot use the menu of a data disc to create an MP3 CD or vice versa. Users would select "Audio CD" to burn music or "Data" to burn documents and files.

CD-RW

Unlike a CD-R, the CD-RW (Compact Disc Rewritable) can be erased and returned to its original blank state. New files can then be copied onto the rewritable disk. CD-RW never became as popular as the CD-R's because they are not compatible with most disc players to listen to music. They are primarily used to move data from one computer to another, or to copy files that are only needed a few times.

Size

A standard CD-ROM, CD-R and CD-RW can hold up to 700MB of data. As an audio CD, it can be used to store up to 80 minutes of music. In comparison, a DVD-ROM can contain 4.7 GB of information and movies.

Warning

Shattering of CD-ROMs while rare, have been known to happen. The incident occurs when discs are used in drives that move at speeds of 48x to 52x. If a CD shatters in the computer during playback or burning, pieces may fly out of the drive and embed into your skin. Manufacturers have tried to build in fail safes to protect users and to prevent CD-ROMs from exploding.

The Parts and the functions of the CD-ROM DRIVE are as follows:

1. Drawer - for loading the media.

2. Metal Case - covering the CD-ROM from dust and for packaging.

3. Clipped Compounds - For connecting the internal devices

4. Simple Jack - connects electric devices together within the CD-ROM

5. Belt - Controls the drawer in & out of the CD-ROM

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6. Focus lens - reads the input media

7. Electric motor - controls the drawer

8. Connection cables

9. Electric Circuit - Supplies current to other electrical parts.

FLOPPY DISK DRIVE

What is Floppy Disk Drive?

A Floppy Disk Drive, or FDD or FD for short, is a computer disk drive that enables a

user to save data to removable diskettes. Although 8" disk drives were first made

available in 1971, the first real disk drives used were the 5 1/4" floppy disk drives, which

were later replaced with 3 1/2" floppy disk drives. Today, because of the limited capacity

and reliability of floppy diskettes many computers no longer come equipped with floppy

disk drives and are being replaced with CD-R, other writable discs, andflash drives.

Above is an example of each of the different floppy drives. As can be seen, the size of

the floppy drive and the diskettes they use have decreased over time.

Types of Floppy Disk Drives

Floppy disk drives are available in different sizes. The floppy disk drive shares the name

with the size of the floppy disk that it uses. For example, the floppy disk drive that uses

the 3.5 inch floppy disk is called the 3.5 inch floppy disk drive.

5.25 Inch Floppy Disk Drive

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Older systems used the 5.25 inch floppy disk drive to read and write data to the 5.25

inch floppy disk. This drive has a lever on the front of the drive that must be turned

clockwise, to lock the floppy disk in after inserting the disk in the drive. You must turn

the lever anti-clockwise to remove the floppy disk from the drive.

3.5 Inch Floppy Disk Drive

The 3.5 inch floppy disk drive can read and write data to the 3.5 inch floppy disk. The

3.5 inch floppy drive spins the floppy disk at a speed of 300 rotations per minute. This

enables the floppy to be formatted with 80 tracks on each side of the disk. Each track is

alienated into 18 sectors. The sector can hold 512 bytes. The 3.5 inch floppy disk drive

also has an eject button that is used to remove the floppy disk from the drive.

The 3.5 inch floppy drive spins the floppy disk at a speed of 300 rotations per minute.

This enables the floppy to be formatted with 80 tracks on each side of the disk. Each

track is separated into 18 sectors. The sector can hold 512 bytes. The 3.5 inch floppy

disk drive also has a button that is used to remove the floppy disk from the drive.

. The 3.5 inch floppy had a high density and could hold 720 KB of data. The floppy disk

was then improved and the density increased to create a high-density floppy disk that

could hold 1.44 MB of data. The 3.5 inch floppy disk was then improved and the double-

sided floppy disk was created that could store data on both sides of the floppy disk.

The 3.5 inch floppy disk has two holes at the bottom of the disk. One enables the floppy

disk drive to identify if the floppy disk has a low density or high density. The other is a

write protect tab of the floppy disk. This tab enables us to protect the data on the floppy

disk from being accidentally modified or erased. Sliding the switch down makes the

floppy disk read only. You must slide the switch upward to enable data to be read and

written to the floppy disk.

Parts of a Floppy Disk Drive

Read/Write Head and Actuator

Floppy diskettes are magnetic media, just like hard drives. Each drive has a recording head that reads and writes data and an actuator that repositions the head when needed. If you have difficulty reading several different disks, you may need to clean the drive head. Although cleaning kits for floppy drives are becoming difficult to find in stores, they still can be purchased online for approximately $6 (as of September 2009).

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Motor

Once a disk is inserted, the motor spins the media. A 3.5-inch floppy disk spins as just 300 RPM, well shy of the 7,200 RPM speeds reached by most desktop hard drives. If your floppy drive fails to spin to that level, confirm that it is properly connected to the computer's power supply. Floppy drives require two connections: one for data and another for power.

Latch or Release Button

In 5.25-inch floppy drives, the drive is closed using a latch once a disk is inserted. The 3.5-inch drives automatically lock when a disk is inserted. To release a disk from a 3.5-inch drive, press the release button. Only do this when the drive activity light is off. In rare instances, it can be possible for a 3.5-inch disk to become stuck in the drive. If this happens, turn the computer off, disconnect the power and data cables from the floppy drive and gently dislodge the stuck disk with a screwdriver.

Data Cable Connector

The 5.25-inch floppy drives use a card connector, which the data cable slides over. While 3.5-inch drives use a pin-based connector that looks similar to the connector found on the back of ATA hard drives. If you attempt to connect a floppy drive to a computer and the drive is not recognized when the computer is on, the data cable is most likely connected backwards. You also can diagnose this by looking at the drive's activity light; it will be on even though the drive is not in use. Look for a red marking at one edge of the data cable. It should line up with the first pin (or first connector for a 5.25-inch drive) on the drive and motherboard. Both are identified by a number or white arrow near the pin.

Power Connector

All floppy drives have separate connectors for data and power. 5.25-inch floppy drives use 4-pin Molex connectors, which are the same as the connectors found on ATA hard drives. The 3.5-inch drives use a smaller 4-pin connector, which is included on most power supplies. Both types of power connectors are keyed, preventing them from being inserted improperly. If your power supply does not have the proper connector for the drive intended, purchase an adapter from a computer supply store.

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CHAPTER SUMMARY:

NIC - Stands for Network Interface Card.

Processor - known as the brain of the computer.

There are 2 types of Processor.

INTEL Processor - common used in Office Suite.

AMD Processor - common used for gaming.

Video Cards - It can be Built in and not Built in.

Power Supply - A power supply unit (PSU) converts mains AC to low-voltage

regulated DC power for the internal components of a computer.

Connectors - It is the part of a cable that plugs into a port or interface to connect

one device to another.

Hard Disk Drive - a data storage device used for storing and

retrieving digital information using rapidly rotating disks (platters) coated with magnetic

material.

CD ROM Drive - it is a place on a computer where a compact disc can be held, read

and played.

Floppy Disk Drive - is a computer disk drive that enables a user to save data to

removable diskettes.

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Chapter Quiz:

Essay:

1. Briefly discuss what NIC. Is?

2. Difference between AMD and INTEL Processor.

3. Discuss what is Jumper Setting?

4. Discuss what is Partitioning?

5. Discuss what is Formatting?

6. What are the different types of Floppy Disk? Explain.

7. What are the Computer Connectors?

8. What is CD ROM Drive?

9. What is the Floppy Disk Drive?

10. What is Power Supply?

***Good Luck!***

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Printers

Printer is the most important output device, which is used to print information on paper.

There are two types of printers:

Impact Printers

Non-Impact Printers

Impact Printers

The printers that print the characters by striking against the ribbon and onto the paper are called impact printers.

Characteristics of Impact Printers are the following:

Very low consumable costs Impact printers are very noisy Useful for bulk printing due to low cost There is physical contact with the paper to produce an image

Dot Matrix Printer

In the market, one of the most popular printers is Dot Matrix Printer because of their ease of printing features and economical price. Each character printed is in form of pattern of Dot's and head consists of a Matrix of Pins of size(5*7, 7*9, 9*7 or 9*9) which comes out to form a character that is why it is called Dot Matrix Printer.

Advantages

Inexpensive Widely Used Other language characters can be printed

Disadvantages

Slow Speed Poor Quality

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Non-impact Printers

The printers that print the characters without striking against the ribbon and onto the paper are called Non-impact Printers. These printers print a complete page at a time, also called as Page Printers.

These printers are of two types:

Laser Printers Inkjet Printers

Characteristics of Non-impact Printers:

Faster than impact printers. They are not noisy. High quality.

Support many fonts and different character size.

Laser Printers

These are non-impact page printers. They use laser lights to produce the dots needed to form the characters to be printed on a page.

Advantages

a. Very high speed. b. Very high quality output. c. Gives good graphics quality. d. Supports many fonts and different

character sizes.

Disadvantage

Expensive. Cannot be used to produce multiple copies of a document in a single printing.

Inkjet Printers

Inkjet printers are non-impact character printers based on a relatively new technology. They print characters by spraying small drops of ink onto paper. Inkjet printers produce high quality output with presentable features.

They make less noise because no hammering is done and these have many styles of printing modes available. Color printing is also

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possible. Some models of Inkjet printers can produce multiple copies of printing also.

The major color in each cartridges are Black, Red/Magenta, Cyan/ Green and Yellow (CYMK).

Advantages

a. High quality printing b. More reliable

Disadvantages

Expensive as cost per page is high Slow as compared to laser printer

Installation of Printers

A computer printer does not work until you install

the included drivers and software. If you have lost

the CD for your printer, you can download the

drivers for your printer and use the drivers to install

your printer. A listing of printer manufacturers and

links to their associated driver’s pages are on our

printer driver page.

Connecting the printer to the computer

Connect the printer to the computer either using a

USB cable, parallel port cable, or SCSI cable and

then connect the power plug to a power outlet.

Today, most all home computer printers are using a

USB cable similar to the example picture.

Tip: If this is a network printer, connect the printer to

a wireless network or the RJ-45 connection.

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Setup printer and install software

Every printer should come with the software used to install a printer in Windows or your

operating system.

1. After everything has been plugged in turn the computer on.

2. Insert the CD that came with the printer. If the CD does not automatically start, open My Computer, double-click on the CD drive, and then click the Setup or Install file. If you have downloaded the drivers, run the downloaded setup file.

3. Follow the installation wizard and once completed your software is installed.

4. Test the printer to make sure it is working.

Installing a printer only using the drivers

If you only want the printer to be installed and none of the extra software programs

you can only install the printer driver by following the steps below.

Tip: A listing of printer drivers and software is on our printer driver page.

Note: if you have installed the printer doing the above steps these steps should

not be necessary unless you encountered errors.

1. With the printer connected and on open the Control Panel.

2. In the Control Panel double-click the Printers or Printers and Fax icon.

3. In the Printers window, click the Add a printer icon.

4. After completing the above steps, you should see the Windows Printer Wizard. Click Next to start the wizard.

5. Next, you have the choice of installing a Local or Network printer. If the printer is connected to your computer choose Local printer attached to this computer and click Next.

6. When prompted for the location of the printer drivers, browse to the directory of your drivers or point it to the printer CD.

Testing the printer

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After the printer is installed, you can use Windows to print a self-test page to help

verify the printer is working.

Microsoft Windows users

1. Click Start, Settings, and open Control Panel.

2. Double-click the Printers or Printers and Fax icon.

3. Right-click on the Printer you want to test and click Properties. If you do not see your printer, your printer is not installed.

4. In the Printers Properties window, click the Print Test Page button.

5. If the printer can print a test page, your printer is installed and setup properly. However, if you are unable to print in other programs the program you are attempting to print from has issues.

10 biggest Printer Problems and how to fix it?

Printers: Can't live with them, can't nuke them. You could always toss a misbehaving

inkjet or laser out the window, but where would that leave you? Truth be told, we need

our printers, despite their maddening quirks. Here's a saner idea: Take a deep breath,

channel your inner tech support rep, and repair that which has failed you. (Cue sitar.)

We've listed the 10 biggest printer annoyances -- of course, your Top 10 list may vary --

and ways to fix them.

Problem: Printing is too slow.

Solution: Rev up printer performance--and save ink in the process--by reducing print

quality for everyday output. While printer settings vary by model, here's how to switch to

draft-printing mode in most Windows apps. Select Print and Properties, and then look

for a setting that reduces print quality. With the HP Photosmart 8450, for instance,

change the default print quality setting from Normal to Fast Draft (click screen-shot at

right). Other speedup suggestions: Print pages from websites without graphics, and add

RAM to your printer, if possible.

Problem: Ink and/or toner costs too much.

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Solution: PC World has written a lot about the printing industry's sneaky practices over

the years. To wit: They snare you with dirt-cheap printers sold at or below cost, and

then stick it to you later with ultra-pricey consumables.

Based on our tests, we can't recommend third party vendors' remanufactured or refilled

ink cartridges, which may not give you your money's worth. One cost-saving solution is

tobuy higher-capacity cartridges. If you print a lot, try an ink cartridge with a 250-plus

page yield, or a toner cartridge with a 2,000-plus page yield.

Problem: Windows is sending print jobs to the wrong printer.

Solution: For some mysterious reason, Windows may select a new default printer--the

one it automatically sends print jobs to. (This happened to me when I upgraded from

Vista to Windows 7.) To fix this glitch in Windows 7, click Start (the Windows icon in the

lower-left corner of the screen) and select Devices and Printers. Under Printers and

Faxes, right-click the printer you want to make the default, and select Set as default

printer.

If you're using earlier versions of Windows, these steps vary a bit.

Problem: My prints are too light, too spotty, or have horizontal lines.

Solution: You may have a clogged print head, a problem that can occur if you use an

inkjet printer infrequently. Your printer's utility program can clean out the dried ink, and

print a test page for inspection. The step-by-step instructions on how to do this vary by

printer. From the Windows 7 Start menu, click Devices and Printers or Control Panel,

and look for your printer's utility app.

Problem: My printer says my ink cartridge is empty. I think it's lying.

Solution: You may be right. Printer out-of-ink messages are notoriously unreliable. The good news: You can try various hacks to get around those ink cartridge controls. We're not suggesting that all, or even some, of these reader tips will work with your printer, but they're worth a try. One tip reveals how to reset ink cartridges for various HP printers. And a video on this page shows how to revive an "out of ink" Epson cartridge. If you're feeling adventurous, check them out.

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Problem: My wireless printer is too slow.

Solution: To get the best performance from a network printer, it's hard to beat a wired, Ethernet-cable-to-router connection. Wireless printing may be more convenient in many homes and offices, but it has its limitations. Since Wi-Fi speeds slow down with distance, you'll want to place your wireless printer as close as possible to the router. Also, make sure your Wi-Fi printer or any wireless print server it connects to supports the 802.11n spec, which can rival the performance of 100-mbps Ethernet.

Problem: I use remanufactured or refilled ink cartridges, and my prints look awful.

Solution: We recommend sticking with the manufacturer's ink. Third-party products may save you money up front, but the consequences can get ugly--literally--if the cheaper inks produce lower-quality prints.

Here's another reason: wasted ink. The PC World Test Center has found that some

cartridges leave more than 40 percent of their ink unused. The worst offenders,

unfortunately, are third-party brands. Printer manufacturers may overcharge

shamelessly for ink, but at least you know what you're getting.

Problem: I don't know how to fit more text on one page. How do I do it?

Solution: Shrinking text to fit two pages on one sheet saves money (you'll buy less

paper) and speeds up printing (fewer pages to print). This two-for-one approach is best

for spreadsheets, receipts, and other documents that are still legible once shrunken.

In any Windows program, select Print and Properties, and then look for a printer setting

that lets you increase the number of pages per sheet.

Problem: Grandma called and wants me to fix her "broken" printer. I'm no tech guru.

What should I do?

Solution: You could always pretend you're not home, but that might lead to bigger

problems down the line. We recommend you help Grandma out, because printer

problems encountered by the, um, technically challenged are often easy to fix.

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First, have her see if the printer is plugged into a wall outlet. (Don't laugh. It's fairly common.) Second, she should make sure there's paper in the tray. And third, have her check the cable (probably USB or Ethernet) that connects the printer to the PC or router. This troubleshooting basics article has more advice.

Problem: My paper tray is flimsy.

Solution: To cut costs on some printers, vendors often include low-capacity or flimsy trays. In her article "Is Your Printer Stealing From You?", PC World's Melissa Riofrio lists seven printers with notoriously cheap paper trays--each from major vendors such as Brother, Dell, Epson, HP, Ricoh, and Xerox. Shame on you guys.

So what can you do? Before buying a printer, examine the paper tray carefully. If it

looks like it'll break after the first sideswipe, it's probably wise to get another model. If

the tray is too small for your printing needs, see if there's a higher-capacity option. Or

you could try this guy's approach to fixing a busted printer.

Laser Printer Symptoms Problems and Solutions

PRINT QUALITY:

Poor print quality is probably one of the most common complaints we hear from our

customers, here are some quick fixes for some of the most common ones:

Symptom: Fuzzy Print is usually caused by damp paper.

Solution: Try printing on freshly unwrapped paper that has not been exposed to any sort

of moisture.

Symptom: The degree of black varies across the page. This is also known as horizontal

variable print density. This can be caused by low toner in the cartridge. Other causes

can be that the printer may not be level or it may be near a strong light source.

Solution: Remove & shake the cartridge to redistribute the toner. Move the printer to a

level spot and one that is less well lit.

Symptom: Vertical variable print density is another typical issue and is sometimes called

“banding.”

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Solutions: The developer roller may be dirty so simply clean the connections.

Symptom: Grey Print is often the result of two likely causes, either the density setting

needs adjustment or the OPC drum is wearing.

Solution: Replace the cartridge.

Symptom: A grey background or a black area of print appears grey. This is generally

caused when too much toner is being applied.

Solution: Reduce the density setting

Symptom: Regularly Spaced Spots (large interval), at least 3 inches. This is generally

caused by a hole or scratch on the OPC drum.

Solution: Replace print cartridge

Symptom: Regular Spaced Spots (small interval), less than 3 inches. This can be

caused by toner on the fuser.

Solution: Replace fuser cleaning pad, clean fuser or replace fuser.

Symptom: Random Spots can be caused by dirt or toner spill in the device.

Solution: Clean the printer.

Symptom: Toner smears when rubbed. Most likely the toner has not been fused to the

paper properly.

Solution: Check and replace the fuser.

2. Mechanical Symptoms

If the problem is not one of print quality, it’s probably a mechanical issue, here are some

common ones:

MISFEEDS:

Misfeeds are probably the most common mechanical issue. Sometimes the printer fails

to feed the paper from the tray, sometimes paper sticks together and then causes jams.

There are several causes and fixes for misfeeds which we will cover here.

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If the paper media is not supported by the printer or the paper is too heavy, too

light, or too smooth you will get jams. Correct the issue by using the correct media

recommended by the manufacturer. Be especially watchful when printing labels,

I’ve seen some printers that just won’t take this kind of media and causes all kinds

of issues including misfeeds and gumming up the rollers.

If the paper is sticking together, simply remove the paper and fan the stack to

reduce curling and sticking.

If repeated misfeeds are occurring, you may be dealing with weak springs in the

paper tray. One trick that may fix this problem is to load more paper onto the tray

so as to compress these springs. If this does not do the trick the springs and/ or

paper tray may need to be replaced. If you need to get a tech out to do this make

sure he checks the rollers while he’s there because worn rollers can also lead to

repeated misfeeds.

Paper Jams

Paper jams are another annoyance we see a lot of. It happens when paper does not

pass through the printer properly. Paper jams can occur when the wrong paper media is

used, the paper is damp, small fragments of paper are in the paper path or the printer,

or oftentimes there seems to be no apparent reason, this last reason can drive you to

drink. Believe me, we do run into “no apparent reason” more times than I care to think

about. But the best solution to this problem is to thoroughly have the printer cleaned out.

Skewed Prints:

Skewed prints occur when the image on the is not aligned on the page. The culprit here

usually is improper paper loading. To correct this condition, remove the paper from the

tray, fan the edges and reload the paper ensuring that the paper is inserted below the

small catches which hold the paper.

IMAGE CORRUPTION

There are quite a few different types of Image Corruption, what we will do here is cover

the more common ones you will probably run across.

The image that printed is not the image you sent from your computer. This is usually the

fault of the computer, not the printer. What happened for some reason is the computer

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sent the wrong commands to the printer. This is not a printer issue but rather a

computer issue, call the IT guy for this one.

Garbled Data is another common symptom that is normally caused by a

communications error occurring when a command is sent to the printer. Best to call the

IT guy on this one too but here are some possible solutions if you want to try your hand

at solving. Check that the printer cable is firmly seated, reset the printer and reprint the

job. Next check to ensure that the communication settings on the printer and computer

are matched and then print a configuration page. If that still does not fix the problem the

printer may have a faulty controller, call your printer repair tech.

Lost Characters, again usually a communication error, try following the same steps as

with Garbled Data.

Wrong Font, communication error, a software error or even a missing font. Call the IT

guy.

Split Graphic Image, this is when the image is split and covers two pages. Cause’s, it’s

either part of the memory on the printer failed or there is insufficient memory to print

complex graphic jobs. To fix you must install more memory in the printer.

Split Text, this condition is rarely caused by the printer but can occur when there is

insufficient memory to print a very large number of characters. Best bet to solve this one

is to install additional printer memory.

So there you have it, some very common problems with some fairly easy fixes but more

importantly, knowing if its the printer or the computer is very important. If all else fails

call your printer tech of choice and make an appointment for him to stop by. If your in

the Northampton, Mass area you can always give Ink & Toner Solutions a call and who

knows we just might be able to give you a solution over the phone. If it can’t be fixed

over the phone we will dispatch our tech to your location usually the next day. We hope

this has cleared up some of the mystery surround laser printer problems.

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Mouse

Mouse is a pointing device that detects two-dimensional motion relative to a surface.

This motion is typically translated into the motion of a pointer on a display, which allows

for fine control of a graphical user interface.

Physically, a mouse consists of an object held in one's hand, with one or more buttons.

Mice often also feature other elements, such as touch surfaces and "wheels", which

enable additional control and dimensional input.

TYPES OF MOUSE

Trackball mouse: Like an upside-down mouse. Rather than roll the mouse around,

you use your thumb or index finger to roll a ball on top of the mouse. The whole

contraption stays stationary, so it doesn’t need a lot of room, and its cord never gets

tangled.

Digital/Wireless mouse - Wireless mouse provide capability of connecting without

cables. That is very useful for gamers as well as others who want room to freely

move their mouse. A button ‘talks’ to the computer with the infrared port that you

just attach yourself. Some newer laptops consist of built-in infrared ports where you

can start employing the mouse without special hardware.

These sorts of mouse include the necessary driver software. You’ll normally be

capable to start using your brand-new mouse during first minutes. Wireless mouse

are optical, taking into account easier movement. Many wireless mouse are

purchased plus a wireless keyboard. When you’ve got a large enough monitor, you

are able to safely sit well back through the computer and still have the capacity to

apply it efficiently.

INSTALLATION OF MOUSE

Before getting started

1. Difficulty of installing computer mouse should be a 1 out of 5. 2. When connecting the PS/2 or Serial mouse, ensure the computer is off; if the mouse is a USB mouse the computer can be off or on during the installation.

Connect cables

PS/2 Mouse 1. Connect the mouse to the PS/2 port on the back of the computer. Today, although many computers are still using PS/2 mice if you're using a USB mouse skip to the next section.

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2. When looking at the back of the computer you'll notice two PS/2 ports next to each other. Verify you're connecting the mouse into the teal or green connection as shown in the picture below. If your PS/2 ports are not color coded the mouse will be the connection furthest away from the left edge of the computer (when looking at it from the back). If the connections are vertical and not horizontal as shown below the mouse connection may be either depending on the case and motherboard. Look for a small symbol next to the port to identify what one is the mouse.

USB Mouse

Connect the USB mouse to the USB ports on the back or front of your computer or if

you are using a USB port hub, connect the mouse to the hub.

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Serial Mouse

Connect the mouse to the serial port on the back of the computer. If the computer has

serial devices currently connected to the computer and the computer has two serial

ports we recommend you use the first serial connection if you encounter problems

connecting the mouse. Once connected depending on your computer setup you may

need to configure the mouse in CMOS setup as found in the next section.

Install software and drivers

Do I need mouse drivers?

Setup in CMOS setup

If you have connected a serial or USB mouse it may be necessary to setup the ports in

CMOS setup.

If the mouse you are using is a serial mouse and it's having issues being detected verify

that the serial ports or COM ports are enabled and assigned properly in CMOS.

If the mouse was a USB mouse, ensure that USB is enabled and if available, also

ensure that the USB Legacy support is also enabled; this allows the mouse to work in

legacy mode, for example, DOS.

TROUBLESHOOTING MOUSE

Instructions

1. Verify that there is no mouse movement at all. If your computer mouse has

stopped moving completely, check the obvious. Make sure the computer mouse

is plugged in completely. If it is, remove the plug and examine for pins that may

be damaged.

2. See that the mouse stops while you're using it. If the mouse is working perfectly

and suddenly stops, check the connection to see if it is loose. If the connection is

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fine, open up the trackball and check for any fuzz or residue trapped in the

trackball chamber. Remove any residue with a cotton swab and alcohol. Remove

the trackball and clean it with the cotton swab and alcohol as well.

3. Observe that the pointer is not working correctly. If the computer mouse pointer

is working in an odd way, check for a virus. Some computer viruses cause the

mouse to not work properly. Download a free anti-virus program at Free-AV to

run a virus scan on the computer.

4. Check the computer mouse driver. Go to "Control Panel" and open the "System"

folder. Choose "Device Driver Tab" and arrow down to "Mouse." Look and see if

the driver is installed. If there is a yellow icon, the mouse has a problem. Un-

install the mouse and reboot the computer. Reinstall the mouse driver and reboot

the computer.

SYMPTOMS AND DIAGNOSIS

Symptom: When you move the mouse the pointer goes a little ways and stops, you have to lift the mouse up and then put it back down to continue scrolling.

Cause: The mouse track ball and potentiometers (the little bars or wheels inside the track ball well) are dirty. You can see the build up when you remove the track ball. This is a normal occurrence for cloth mouse pads and Track ball pointing devices.

Fix: Clean the gunk from the bars or wheels, this will be a normal occurrence as long as you use a cloth mouse pad.

Symptom: The mouse is very slow to track from one side of the screen to the other.

Cause: The acceleration factor is to low or disabled

Fix: In the Control Panel, go to the Mouse icon, open it, go to the 'Pointer Options' use the slide bar to set the pointer speed. For those that want the pointer to be very precise when selecting a target click on the box 'Enhance pointer precision.

Symptom: Mouse not present after startup.

Cause: The cable became disconnected or the mouse did not initialize (the hardware was not found at startup) or you mouse may have failed.

Fix: Power down the computer, check the cable from the mouse to the port - PS2 mice use the same connector as the keyboard, check that the mouse and keyboard are in the correct ports.

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USB mice, check the mouse cable, if it is chained to more than one device (one device connected to another then that is connected to another, and so on like this: the mouse is connected to the keyboard, the keyboard is connected to the monitor, the monitor is connected to an external USB hub which in turn is connected to the computer.) Restart the computer, is the mouse back?

No, see if you have another mouse with the same connector (PS2 or USB) and try that in the port. Did the mouse come back? Yes - the original mouse has failed. No - the mouse port or controller on the motherboard has failed.

Symptom: Wireless mouse not functioning.

Cause: The wireless mouse works on a radio frequency. The mouse has a transmitter only. Connected to a port (normally a USB port) is a receiver. So when a wireless mouse doesn't work it will be the fact that the mouse isn't transmitting or the mouse transmissions are not getting to the receiver.

Fix: The first thing to do is replace the battery in the mouse. Did this fix your mouse? Yes -done.

No? Then you are having receiver problems. Try using the mouse from a different position relative to the receiver. Did the mouse work? Yes- there is something blocking the mouse transmissions - you will have to reposition the mouse receiver that is connected to the computer. Suggestion - if it is a USB device the get a USB extension cable and use that to move the receiver to a better position.

You will find more troubleshooting mouse techniques in the Self Computer Repair Unleashed! 2nd Edition..

Did the mouse work? No - power down the computer disconnect if a USB device plug into a different port, restart the computer. Did the mouse work? Yes - Done! No? The mouse has failed and requires replacement.

Note: Before you replace the mouse try it on a different computer, if it works on a different computer you may need to uninstall the mouse from the original computer and reinstall it, it is rare that the drivers become corrupt but it does happen.

Symptom: Mouse is intermittent, or disappears while the computer is running.

Cause: USB or PS/2 loose connector or failing mouse or mouse port. Fix: With the computer powered down disconnect the mouse from the computer, if it is a USB mouse move the mouse to another port or swap another USB device into that port. Power up the computer, is it fixed?

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No: PS/2 mouse, try another mouse. If it still is intermittent then the mouse port on the motherboard has failed. USB mouse, if it is still intermittent the mouse has failed.

Troubleshooting a pointing device is very easy, the pointing device and the keyboard are the most used devices connected to the computer eventually they will wear out because they are mechanical devices. Even the wireless mice will fail.

Last point: Wireless mice and keyboards are becoming common in this wireless age if you are experiencing intermittent connections replace the battery or batteries. When you change them be sure to press the "reset" button on the device or it will not connect to the transmitter/receiver connected to the USB port.

CHAPTER SUMMARY

Printers - is the most important output devices, which is used to print an information.

There are two types of Printer.

Impact Printer

Non - Impact Printer

Under Impact Printer is the Dot Matrix.

Dot Matrix Printer - . Each of character printed is in form of pattern of Dot's and head consists of a Matrix of Pins of size (5*7, 7*9, 9*7 or 9*9) which comes out to form a character that is why it is called Dot Matrix Printer.

Under Non-Impact Printers are Inkjet Printer and Laser Printer.

Inkjet Printer - it is a non-impact character printers based on a relatively new technology. They print characters by spraying small drops of ink onto paper. Inkjet printers produce high quality output with presentable features.

Laser Printer - They use laser lights to produce the dots needed to form the characters to be printed on a page.

Mouse - is a pointing device that detects two-dimensional motion relative to a surface.

Note that the color of PS2 mouse is Color Green, and the Keyboard is Violet.

Digital Mouse - is a cordless or wireless Mouse.

Trackball Mouse - it is like an upside-down mouse. Rather than roll the mouse around, you use your thumb or index finger to roll a ball on top of the mouse.

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CHAPTER QUIZ

Multiple Choice:

1. It is the most important output devices.

a. Monitor b. Speaker c. Printer d. None

2. It is the color of port of Mouse.

a. Green b. Red c. Violet d. Black

3. It is the color of ink of Inkjet Printer.

a. Black, Magenta,Cyan,Yellow c. Black, Red, Blue, Green

b. Black, Grey, Pink, Blue d. Black, White, Red, Blue

4. It is a pointing device and input device.

a. Keyboad b. Joystick c. Mouse d. Microphone

5. It is like an upside down mouse.

a. Digital Mouse b. Trackball Mouse c. Optical Mouse d. None

Enumeration:

1-2. Types of Printer

3-4. Non- Impact Printer

5. Impact Printer

6-7. Two types of Mouse.

8-10. Types of Mouse Port

***Good Luck!***

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SOFTWARE INSTALLATION

Installation of Computer Programs

Installation (or setup) of a computer program (including device drivers and plugins), is

the act of making the program ready for execution. Because the process varies for each

program and each computer, programs (including operating systems) often come with

an installer, a specialized program responsible for doing whatever is needed for their

installation. Installation may be part of a larger software deployment process.

Installation typically involves code being copied/ generated from the installation files to

new files on the local computer for easier access by the operating system. Because

code is generally copied/generated in multiple locations, uninstallation usually involves

more than just erasing the program folder. For example, registry files and other deep

code in the system may need to be modified/ deleted for a complete uninstallation.

How to Install a Program?

How to install a software program can depend on the operating system being used and

the program being installed. Because of all the different possibilities, we have created

the steps below as guidelines for installing programs in each of the major operating

systems.

Notice: This document has been created as a basic overview on how to install software

programs, games, and utilities on your computer. If errors are encountered during the

installation, this document will not cover those errors. Use our Search to find any

information about error messages.

General Tips

Microsoft Windows users

MS-DOS Users

General Tips

Make sure your computer meets the system requirements of the program, game, or utility you are attempting to install.

The manuals for the program or the readme file located in the same directory as the install commonly contain exact instructions on how to install a program.

After installing or during the installation, a program may need to install other programs, files, or utilities before it can run. If this is the case, the program prompts you to install the program or you may need to run a separate install before the program can be fully used.

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When installing a program, utility, or game, it is always a good idea first to close or disable any other programs that are running.

After installing a new program if it prompts you to reboot the computer, do it.

Microsoft Windows users

Many software programs, games, and utilities have an AutoPlay feature that will

automatically start the setup screen for the software program when the CD is

placed in the computer. If your program, game, or utility contains this feature, run

the installation through the screen that appears after inserting the disc.

If you are installing a program, game, or utility that does not contain this feature or

you are installing a program from a floppy diskette, follow the steps below. 1. Open My Computer. 2. Within the My Computer window, open the drive that contains the installation

files. For example, if the files are on a floppy diskette, open the A: drive. If they're on a CD or DVD open the D: drive or the letter of the disc drive.

3. Within the drive that contains your files, locate either a setup or install file. Double-clicking on this file should start the installation for the program, game, or utility. If you see multiple setups or install files, try to locate the Application file or double-click each of setup or install files until you find the file that starts the installation. Many times the icons associated with the installation files have the same name.

An alternate method of starting the installation in Microsoft Windows 1. Click Start and Run. 2. In the Run Window, type x:\setup or x:\install where x is the letter of the drive

you want to start the installation. For example, if you are attempting to install a program from the floppy disk drive you would type a:\setup or a:\install. Usually with a CD or DVD it would be d:\setup but may be a different drive letter depending on your computer configuration.

MS-DOS users

Users installing a program from Microsoft DOS should have a basic understanding

of the MS-DOS commands. If you are unfamiliar with any of the commands listed

below, click the link to get additional information and examples on the commands. 1. Before installing a program in MS-DOS, you must switch to the drive or

directory that contains the installation files. If you are installing a program from a CD or diskette, switch to that drive. If the installation files are located in a different directory, use the dir command to list the directories and the cd command to switch into the appropriate directory.

2. Once you are in the directory or drive that contains the installation files, run the executable for the setup. Many times this can be done by typing setup or install at the prompt to start the installation. If both of these commands give a bad command or file name error message, type dir

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*.exe or dir *.com or dir *.bat. These commands will list any executable files; if any files are listed, execute these files to run the installation or setup of the program. If no files are listed when typing all three of the above commands, you are in the incorrect directory or drive letter for that program.

Types of Installation

Attended Installation

On Windows systems, this is the most common form of installation. An installation

process usually needs a user who attends it to make choices, such as accepting or

declining an end-user license agreement (EULA), specifying preferences such as the

installation location, supplying passwords or assisting in product activation. In graphical

environments, installers that offer a wizard-based interface are common. Attended

installers may ask users to help mitigate the errors. For instance, if the disk in which the

computer program is being installed was full, the installer may ask the user to specify

another target path or clear enough space in the disk.

Silent Installation

Installation that does not display messages or windows during its progress. "Silent

installation" is not the same as "unattended installation" (see below): All silent

installations are unattended but not all unattended installations are silent. The reason

behind a silent installation may be convenience or subterfuge. Malware is almost always

installed silently.

Unattended Installation

Installation that is performed without user interaction during its progress or with no user

present at all. One of the reasons to use this approach is to automate the installation of

a large number of systems. An unattended installation either does not require the user

to supply anything or has received all necessary input prior to the start of installation.

Such input may be in the form of command line switches or an answer file, a file that

contains all the necessary parameters. Windows XP and most Linux distributions are

examples of operating systems that can be installed with an answer file. In unattended

installation, it is assumed that there is no user to help mitigate errors. For instance, if the

installation medium was faulty, the installer should fail the installation, as there is no

user to fix the fault or replace the medium. Unattended installers may record errors in

a computer log for later review.

Headless Installation

Installation performed without using a computer monitor connected. In attended forms of

headless installation, another machine connects to the target machine (for instance, via

a local area network) and takes over the display output. Since a headless installation

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does not need a user at the location of the target computer, unattended headless

installers may be used to install a program on multiple machines at the same time.

Scheduled or Automated Installation

An installation process that runs on a preset time or when a predefined condition

transpires, as opposed to an installation process that starts explicitly on a user's

command. For instance, a system administrator willing to install a later version of a

computer program that is being used can schedule that installation to occur when that

program is not running. An operating system may automatically install a device driver

for a device that the user connects. (See plug and play.) Malware may also be installed

automatically. For example, the infamous Conficker was installed when the user

plugged an infected device to their computer.

Clean Installation

A clean installation is one that is done in the absence of any interfering elements such

as old versions of the computer program being installed or leftovers from a previous

installation. In particular, the clean installation of an operating system is an installation in

which the target disk partition is erased before installation. Since the interfering

elements are absent, a clean installation may succeed where an unclean installation

may fail or may take significantly longer.

Network Installation

Not to be confused with network booting.

Network installation, shortened net install, is an installation of a program from a shared

network resource that may be done by installing a minimal system before proceeding to

download further packages over the network. This may simply be a copy of the original

media but software publishers which offer site licenses for institutional customers may

provide a version intended for installation over a network.

WINDOWS

It is a user friendly operating system.

Here are the steps in Installing Windows 7.

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Installing Windows 7 for Beginners

1. Turn your computer on then press Del

or F2 (depend on your computer’s mainboard)

to enter the system BIOS

2. Go to Boot menu and choose

Boot From CD/DVD.

3. Press F10 to save the configuration

and exit BIOS then reset your computer.

4. Insert Windows 7 DVD into your

DVD drive then start up your

computer, Windows 7 will be

loading files.

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5. Select these parts: Language to Install,

Time and currency format, Keyboard or input

method. Then click Next.

6. Choose Install Now if you want to

install Windows 7. Choose the

Windows 7 version that you want

to install in 'Select the operating

system you want to install' . Here

we choose Windows 7 Ultimate

then click next (depending on

your Windows DVD, this step is

an option).

7. Click 'I accept the license terms' in

'Please read the license' then click Next.

8. Choose 'Upgrade' in 'Which type

of installation do you want' if you

want to upgrade from an older

Windows version to Windows 7,

'Custom (advance)' if you want to

install a new version of Windows.

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9. Choose Partition for installation, if

your computer has only one hard disk, it

will be easy for selection, but if it has

some Partition, you will have to consider

which Partition to choose.

10. Wait for Installing Windows to

progress. Your computer might be

restarted during the process.

11. Type you’re a user account and

computer name. After click Next.

12. Type a password for your account,

you can also Type a password hint to

help in case of forgetting the password

in the future, and then click Next.

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13. Type in activation code or key for your

license in Product key box if you have

any. Click Next.

14. Choose how to protect your

Windows. Here we choose Use

recommended settings.

15. Set up your Time zone then click Next.

16. Choose an option from 3

choices: Public Network, Work

Network, Home Network. Choose

Home Network for using Internet

at home.

Method 1 of 2: Hardware requirements

This is minimum hardware that you need to have on your computer and should be

checked in advance of installing.

1 GHz CPU with 32 bits or 64 bits.

1 GB Ram for 32 bits or 2 GB Ram for 64 bits.

16 GB empty space hard disk for 32 bits or 20 GB for 64 bits.

DVD drive (if installing from a DVD).

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Method 2 of 2: Some errors during Windows 7 installation

After Windows 7 installation, if you cannot connect to Internet, please check these

troubleshooting:

Make sure Internet cable and the modem are working properly, the connection

points are not getting loose.

Check the network drive (normally Windows 7 automatically detects drivers).

Set up Windows IP if the modem doesn’t analyze it automatically (searching on

Internet for how to set it up)

Some devices might not work such as: USB 3.0, Webcam, Bluetooth etc. then you

should check the driver ok to see if it has been installed properly.

SYSTEM SOFTWARE AND DRIVERS

SYSTEM SOFTWARE

System software (systems software) is computer software designed to operate and

control the computer hardware and to provide a platform for running application

software. System software can be separated into two different categories, operating

systems and utility software.

The operating system (prominent examples being z/OS, Microsoft Windows, Mac OS X and Linux), allows the parts of a computer to work together by performing tasks like transferring data between memory and disks or rendering output onto a display device. It also provides a platform to run high-level system software and application software.

A kernel is the core part of the operating system that defines an API for applications programs (including some system software) and an interface to device drivers.

Device drivers such as computer BIOS and device firmware provide basic functionality to operate and control the hardware connected to or built into the computer.

A user interface "allows users to interact with a computer." Since the 1980s the graphical user interface (GUI) has been perhaps the most common user interface technology. The command-line interface is still a commonly used alternative.

Utility software helps to analyze, configure, optimize and maintain the computer, such as virus protection.

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In some publications, the term system software also includes software development tools (like a compiler, linker or debugger).

In contrast to system software, software that allows users to do things like create text documents, play games, listen to music, or web browsers to surf the web are calledapplication software. The line where the distinction should be drawn isn't always clear. Most operating systems bundle such software. Such software is not considered system software when it can be uninstalled without affecting the functioning of other software. Exceptions could be e.g. web browsers such as Internet Explorer where Microsoft argued in court that it was system software that could not be uninstalled. Later examples are Chrome OS and Firefox OS where the browser functions as the only user interface and the only way to run programs (and other web browser can not be installed in their place), then they can well be argued to be (part of) the operating system and then system software.

DRIVERS

In computing, a device driver (commonly referred to as simply a driver) is a computer program that operates or controls a particular type of device that is attached to a computer. A driver provides a software interface to hardware devices, enabling operating systems and other computer programs to access hardware functions without needing to know precise details of the hardware being used.

A driver typically communicates with the device through the computer bus or communications subsystem to which the hardware connects. When a calling program invokes a routine in the driver, the driver issues commands to the device. Once the device sends data back to the driver, the driver may invoke routines in the original calling program. Drivers are hardware-dependent andoperating-system-specific. They usually provide the interrupt handling required for any necessary asynchronous time-dependent hardware interface.

APPLICATIONS

Because of the diversity of modern hardware and operating systems, drivers operate in many different environments. Drivers may interface with:

printers

video adapters

Network cards

Sound cards

Local buses of various sorts—in particular, for bus mastering on modern systems

Low-bandwidth I/O buses of various sorts (for pointing devices such as mice, keyboards, USB, etc.)

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Computer storage devices such as hard disk, CD-ROM, and floppy disk buses (ATA, SATA, SCSI)

Implementing support for different file systems

Image scanners

Digital cameras

Common levels of abstraction for device drivers include:

For hardware:

Interfacing directly

Writing to or reading from a device control register

Using some higher-level interface (e.g. Video BIOS)

Using another lower-level device driver (e.g. file system drivers using disk drivers)

Simulating work with hardware, while doing something entirely different

For software:

Allowing the operating system direct access to hardware resources

Implementing only primitives

Implementing an interface for non-driver software (e.g., TWAIN)

Implementing a language, sometimes quite high-level (e.g., PostScript)

So choosing and installing the correct device drivers for given hardware is often a key component of computer system configuration.

OPEN DRIVER

Printers: CUPS

RAIDs: CCISS (Compaq Command Interface for SCSI-3 Support)

Scanners: SANE

Video: Vidix, Direct Rendering Infrastructure

Solaris descriptions of commonly used device drivers

fas: Fast/wide SCSI controller

hme: Fast (10/100 Mbit/s) Ethernet

isp: Differential SCSI controllers and the SunSwift card

glm: (Gigabaud Link Module) UltraSCSI controllers

scsi: Small Computer Serial Interface (SCSI) devices

sf: soc+ or social Fiber Channel Arbitrated Loop (FCAL)

soc: SPARC Storage Array (SSA) controllers

social: Serial optical controllers for FCAL (soc+)

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APIs

Windows Display Driver Model (WDDM) – the graphic display driver architecture for Windows Vista, Windows 7 and Windows 8.

Windows Driver Foundation (WDF)

Windows Driver Model (WDM)

Network Driver Interface Specification (NDIS) – a standard network card driver API

Advanced Linux Sound Architecture (ALSA) – as of 2009 the standard Linux sound-driver interface

Scanner Access Now Easy (SANE) – a public-domain interface to raster-image scanner-hardware

I/O Kit – an open-source framework from Apple for developing Mac OS X device drivers

Installable File System (IFS) – a filesystem API for IBM OS/2 and Microsoft Windows NT

Open Data-Link Interface (ODI) – a network card API similar to NDIS

Uniform Driver Interface (UDI) – a cross-platform driver interface project

Dynax Driver Framework (dxd) – C++ open source cross-platform driver framework for KMDF and IOKit

CHAPTER SUMMARY

Installation - setup of Computer Program.

7 types of Installation.

Attended Installation

Silent Installation

Unattended Installation

Headless Installation

Scheduled or Automated Installation

Clean Installation

Network Installation

System software (systems software) is computer software designed to operate and

control the computer hardware and to provide a platform for running application

software. System software can be separated into two different categories, operating

systems and utility software.

DRIVERS - a software component that lets the operating system and a device

communicate with each other.

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CHAPTER QUIZ

Defnition of Terms:

1. Instalation

2. Windows

3. System software

4. Driver

Enumeration:

5.

6.

7.

8. 7 types of Installation

9.

10.

11.

12.

13. 4 Sample of Open Drivers

14.

15.

***GOOD LUCK!***

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Networking Basics

Overview

Computer networking has become an integral part of business today. Individuals,

professionals and academics have also learned to rely on computer networks for

capabilities such as electronic mail and access to remote databases for research and

communication purposes. Networking has thus become an increasingly pervasive,

worldwide reality because it is fast, efficient, reliable and effective. Just how all this

information is transmitted, stored, categorized and accessed remains a mystery to the

average computer user.

TYPES OF NETWORKS

SAN(Storage Area Network) - Storage Area

Network are primarily used as information

databases. They are not usually used by large

organizations or similar entities. They are

specifically used for the storage of information, and

easy retrieval of specific pieces of data whenever

required. Storage Area Networks are usually used

by websites which offer downloading services.

SANs (System Area Networks) - System Area

Networks are speed oriented networks which

provide high speed internet connections to a cluster of

computers. These are primarily used for server

purposes, and allow other computers to connect to

these System Area Networks. Permission to different

access points are given according to what status a

system is on the System Area Network, such as

administrators or simple users.

LANs (Local Area Network) - A network is any

collection of independent computers that exchange

information with each other over a shared

communication medium. Local Area Networks or LANs

are usually confined to a limited geographic area, such

as a single building or a college campus. LANs can be

small, linking as few as three computers, but can often

link hundreds of computers used by thousands of

people. The development of standard networking

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protocols and media has resulted in worldwide proliferation of LANs throughout

business and educational organizations.

MAN (Metropolitan Area Networks) -

Metropolitan Area Networks are not commonly

used these days, they are used to create

communication between systems in an entire city.

Hence a Metropolitan Area Network area falls

between the sizes Local Area Networks, and

Wide Area Networks. Metropolitan Area Networks

are used by city specific businesses such as the

New York Times in the state of New York.

WAN (Wide Area Networks) - Wide Area

Networks are used to connect server machines

and computers across continents are countries

for constant information updates. Wide Area

Networks, are used across the globe, many

networks connect with one another across

continents to create one giant Wide Area

Network. Wide Area Networks use optic fibre as

their communication medium. The largest

example of a Wide Area Network is the internet

itself, which connects all users to the information and data that is available on the

internet.

NETWORK DEVICES

Modems

A modem is a device that makes it possible for computers to communicate over telephone lines. The word modem comes from Modulate and Demodulate. Because standard telephone lines use analog signals, and computers digital signals, a sending modem must modulate its digital signals into analog signals. The computers modem on the receiving end must then demodulate the analog signals into digital signals. Modems can be external, connected to the

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computers serial port by an RS-232 cable or internal in one of the computers expansion slots. Modems connect to the phone line using standard telephone RJ-11 connectors.

HUB

Networks using a Star topology require a central point for the devices to connect. Originally this device was called a concentrator since it consolidated the cable runs from all network devices. The basic form of concentrator is the hub.

As shown in Figure; the hub is a hardware device that contains multiple, independent ports that match the cable type of the network. Most common hubs interconnect Category 3 or 5 twisted-pair cable with RJ-45 ends, although Coax BNC and Fiber Optic BNC hubs also exist. The hub is considered the least common denominator in device concentrators. Hubs offer an inexpensive option for transporting data between devices, but hubs don't offer any form of intelligence. Hubs can be active or passive. An active hub strengthens and regenerates the incoming signals before sending the data on to its destination. Passive hubs do nothing with the signal.

Ethernet Hubs

An Ethernet hub is also called a multiport repeater. A repeater is a device that amplifies a signal as it passes through it, to counteract the effects of attenuation. If, for example, you have a thin Ethernet network with a cable segment longer than the prescribed maximum of 185 meters, you can install a repeater at some point in the segment to strengthen the signals and increase the maximum segment length. This type of repeater only has two BNC connectors, and is rarely seen these days.

8 Port mini Ethernet Hub The hubs used on UTP Ethernet networks are repeaters as well, but they can have many RJ45 ports instead of just two BNC connectors. When data enters the hub through any of its ports, the hub amplifies the signal and transmits it out through all of the other ports. This enables a star network to have a shared medium, even though each computer has its own separate cable. The hub relays every packet transmitted by any computer on the network to all of the other computers, and also amplifies the signals. The maximum segment length for a UTP cable on an Ethernet network is 100 meters. A segment is defined as the distance between two communicating computers. However,

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because the hub also functions as a repeater, each of the cables connecting a computer to a hub port can be up to 100 meters long, allowing a segment length of up to 200 meters when one hub is inserted in the network.

Switches

Switches are a special type of hub that offers an additional layer of intelligence to basic, physical-layer repeater hubs. A switch must be able to read the MAC address of each frame it receives. This information allows switches to repeat incoming data frames only to the computer or computers to which a frame is addressed. This speeds up the network and reduces congestion.

Switches operate at both the physical layer and the data link layer of the OSI Model.

REPEATERS

A repeater is an object that increases a signal's strength, so it can be transmitted and received over a greater distance without a loss in quality. These devices are commonly used with networks to help the lines running between network devices reach farther destinations.

Routers

Routers Are networking devices used to extend or segment networks by forwarding packets from one logical network to another. Routers are most often used in large internetworks that use the TCP/IP protocol suite and for connecting TCP/IP hosts and local area networks (LANs) to the Internet using dedicated leased lines.

Routers work at the network layer (layer 3) of the Open Systems Interconnection (OSI) reference model for networking to move packets between networks using their logical addresses (which, in the case of TCP/IP, are the IP addresses of destination hosts on the network). Because routers operate at a higher OSI level than bridges do, they have

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better packet-routing and filtering capabilities and greater processing power, which results in routers costing more than bridges.

Routing tables

Routers contain internal tables of information called routing tables that keep track of all known network addresses and possible paths throughout the internetwork, along with cost of reaching each network. Routers route packets based on the available paths and their costs, thus taking advantage of redundant paths that can exist in a mesh topology network. Because routers use destination network addresses of packets, they work only if the configured network protocol is a routable protocol such as TCP/IP or IPX/SPX. This is different from bridges, which are protocol independent. The routing tables are the heart of a router; without them, there's no way for the router to know where to send the packets it receives. Unlike bridges and switches, routers cannot compile routing tables from the information in the data packets they process. This is because the routing table contains more detailed information than is found in a data packet, and also because the router needs the information in the table to process the first packets it receives after being activated. A router can't forward a packet to all possible destinations in the way that a bridge can.

Static routers: These must have their routing tables configured manually with all network addresses and paths in the internetwork.

Dynamic routers: These automatically create their routing tables by listening to network traffic.

Routing tables are the means by which a router selects the fastest or nearest path to the next "hop" on the way to a data packet's final destination. This process is done through the use of routing metrics.

Routing metrics which are the means of determining how much distance or time a packet will require to reach the final destination. Routing metrics are provided in different forms.

hop is simply a router that the packet must travel through.

Ticks measure the time it takes to traverse a link. Each tick is 1/18 of a second. When the router selects a route based on tick and hop metrics, it chooses the one with the lowest number of ticks first.

You can use routers, to segment a large network, and to connect local area segments to a single network backbone that uses a different physical layer and data link layer standard. They can also be used to connect LAN's to a WAN's.

TYPES OF COMPUTER NETWORK TOPOLOGY

The physical topology of a network refers to the configuration of cables, computers, and other peripherals. Physical topology should not be confused with logical topology which

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is the method used to pass information between workstations. Logical topology was discussed in the Protocol chapter.

Star Topology:

All the cables run from the computers to

a central location, where they are all

connected by a device called a hub. Each

computer on a star network

communicates with a central hub that

resends the message either to all the

computers or only to the destination

computers. Hub can be active or passive

in the star network Active hub

regenerates the electrical signal and

sends it to all the computers connected to

it. Passive hub does not amplify or

regenerate signal and does not require electrical power to run. We can expand a star

network by placing another star hub.

Advantages:

Easy to modify and add new computers to a star net

Center of a star net is a good place to diagnose network faults

Single computer failure do not necessarily bring down the whole net

Several cable types can be used with the hub

Disadvantages:

Central hub fails, the whole network fails to operate

Many star networks require a device at the central point to rebroadcast or switch network traffic.

Costs more for cabling in star net than bus.

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Ring Topology:

Each computer is connected to the next

computer ,with the last one connected to

the first. Every computer is connected to

the next computer in the ring, and each

retransmits what it receives from the

previous computer. The message flow

around the ring in one direction. Some

ring networks do token passing. It passes

around the ring until a computer wishes to

send information to another computer.

The computer adds an electronic address

and data and sends it around the ring.

Each computer in sequence receives the

token and the information and passes

them to the next until either the electronic

address matches the address of the

computer or the token returns to the origin. The receiving computer returns a message

to the originator indicating that the message has been received. The sending computer

then creates another token and place it on the network, allowing another station to

capture the token and being transmitted.

Advantages:

No computer can monopolize the network

The fair sharing of the network allows the net to degrade gracefully as more user are added.

Disadvantages:

Failure of one compute can affect the total network

Difficult to troubleshoot

Adding or removing Computers disrupts the network

Bus Topology:

All the devices on a bus topology are

connected by one single cable. When one

computer sends a signal up the wire, all the

computers on the network receive the

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information, but only one accepts the information. The rest regrets the message. One

computer can send a message at a time. A computer mustwait until the bus is free

before it can transmit. When the signal reaches the end of the wire, it bounces back and

travels back up the wire. When a signal echoes back and forth along an unterminated

bus, it is called ringing. To stop the signals from ringing, attach terminators at either end

of the segment. The terminators absorb the electrical energy and stop the reflection.

Advantages and disadvantages of network topology:

Advantage of network topology

1. The bus is simple, reliable in small network, easy to use and understand

2. Requires the least amount of cable to connect the computers and less expensive

3. Easy to extend the bus

Disadvantage of network topology

1. Heavy network traffic can slow a bus considerably

2. Each barrel connector weakens the electrical signal

3. Difficult to troubleshoot a bus

Mesh Topology:

The mesh topology connects all devices (nodes) to

each other for redundancy and fault tolerance. It is

used in WANs to interconnect LANs and for mission

critical networks like those used by banks and

financial institutions. Implementing the mesh

topology is expensive and difficult.

Advantages:

Fault tolerance

Guaranteed communication channel capacity

Easy to troubleshoot

Disadvantages:

Difficulty of installation and reconfiguration

Cost of maintaining redundant link

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TOKEN RING

Token ring or 802.5 is a network where all computers are connected in a circular fashion. The term token is used to describe a segment of information that is sent through that circle; when a computer on the network can decode that token, it receives data. The token ring is used by ARCNET, token bus and FDDI. Today, 802.5 and Token ring are considered inactive.

Token ring local area network (LAN) technology is

a protocol which resides at the data link layer (DLL) of the OSI model. It used a special three-byte frame called a token that travels around the ring. Token-possession grants the possessor permission to transmit on the medium. Token ring frames travel completely around the loop.

Initially used only in IBM computers, it was eventually standardized with protocol IEEE 802.5.

The data transmission process goes as follows:

Empty information frames are continuously circulated on the ring.

When a computer has a message to send, it seizes the token. The computer will then be able to send the frame.

The frame is then examined by each successive workstation. The workstation that identifies itself to be the destination for the message copies it from the frame and changes the token back to 0.

When the frame gets back to the originator, it sees that the token has been changed to 0 and that the message has been copied and received. It removes the message from the frame.

The frame continues to circulate as an "empty" frame, ready to be taken by a workstation when it has a message to send.

The token scheme can also be used with bus topology LANs.

NETWORK INTERFACE CARD INSTALLATION

1. Open the PC case. The power should be

off when you do this.

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2. Ensure that you have an antistatic wrist

strap attached to your wrist and

grounded to the PC when working with

it.

3. Remove the strap before you switch on

the power.

4. Now take the NIC card and install it

into one of the PCI slots by aligning the

guide notches with the PCI slot.

5. Press straight down with gentle

pressure until the card snugly fits into

the PCI slot.

6. Secure the card with a single screw used

to attach the card to the PC.

7. Check the card whether it moves

from its position. If it does, it

could damage itself when the PC

is turned on.

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8. Close the PC case and turn on the

power.

9. Check if the internet works or

not. If not then check the

connections and repeat the above

steps.

CABLING

What is Network Cabling?

Cable is the medium through which information usually moves from one network device to another. There are several types of cable which are commonly used with LANs. In some cases, a network will utilize only one type of cable, other networks will use a variety of cable types. The type of cable chosen for a network is related to the network's topology, protocol, and size. Understanding the characteristics of different types of cable and how they relate to other aspects of a network is necessary for the development of a successful network.

The following sections discuss the types of cables used in networks and other related topics.

Unshielded Twisted Pair (UTP) Cable Shielded Twisted Pair (STP) Cable Coaxial Cable Fiber Optic Cable Cable Installation Guides Wireless LANs Unshielded Twisted Pair (UTP) Cable

Twisted pair cabling comes in two varieties: shielded and unshielded. Unshielded twisted pair (UTP) is the most popular and is generally the best option for school networks (See fig. 1).

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Fig.1. Unshielded twisted pair

The quality of UTP may vary from telephone-grade wire to extremely high-speed cable. The cable has four pairs of wires inside the jacket. Each pair is twisted with a different number of twists per inch to help eliminate interference from adjacent pairs and other electrical devices. The tighter the twisting, the higher the supported transmission rate and the greater the cost per foot. The EIA/TIA (Electronic Industry Association/Telecommunication Industry Association) has established standards of UTP and rated six categories of wire (additional categories are emerging).

Categories of Unshielded Twisted Pair

Category Speed Use

1 1 Mbps Voice Only (Telephone Wire)

2 4 Mbps LocalTalk & Telephone (Rarely used)

3 16 Mbps 10BaseT Ethernet

4 20 Mbps Token Ring (Rarely used)

5 100 Mbps (2 pair) 100BaseT Ethernet

1000 Mbps (4 pair) Gigabit Ethernet

5e 1,000 Mbps Gigabit Ethernet

6 10,000 Mbps Gigabit Ethernet

Unshielded Twisted Pair Connector

The standard connector for unshielded twisted pair cabling is an RJ-45 connector. This is a plastic connector that looks like a large telephone-style connector (See fig. 2). A slot allows the RJ-45 to be inserted only one way. RJ stands for Registered Jack, implying that the connector follows a standard borrowed from the telephone industry. This standard designates which wire goes with each pin inside the connector.

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Fig. 2. RJ-45 connector

Shielded Twisted Pair (STP) Cable

Although UTP cable is the least expensive cable, it may be susceptible to radio and electrical frequency interference (it should not be too close to electric motors, fluorescent lights, etc.). If you must place cable in environments with lots of potential interference, or if you must place cable in extremely sensitive environments that may be susceptible to the electrical current in the UTP, shielded twisted pair may be the solution. Shielded cables can also help to extend the maximum distance of the cables.

Shielded twisted pair cable is available in three different configurations:

1. Each pair of wires is individually shielded with foil. 2. There is a foil or braid shield inside the jacket covering all wires (as a group). 3. There is a shield around each individual pair, as well as around the entire group

of wires (referred to as double shield twisted pair).

Coaxial Cable

Coaxial cabling has a single copper conductor at its center. A plastic layer provides insulation between the center conductor and a braided metal shield (See fig. 3). The metal shield helps to block any outside interference from fluorescent lights, motors, and other computers.

Fig. 3. Coaxial cable

Although coaxial cabling is difficult to install, it is highly resistant to signal interference. In addition, it can support greater cable lengths between network devices than twisted pair cable. The two types of coaxial cabling are thick coaxial and thin coaxial.

Thin coaxial cable is also referred to as thinnet. 10Base2 refers to the specifications for thin coaxial cable carrying Ethernet signals. The 2 refers to the approximate maximum

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segment length being 200 meters. In actual fact the maximum segment length is 185 meters. Thin coaxial cable has been popular in school networks, especially linear bus networks.

Thick coaxial cable is also referred to as thicknet. 10Base5 refers to the specifications for thick coaxial cable carrying Ethernet signals. The 5 refers to the maximum segment length being 500 meters. Thick coaxial cable has an extra protective plastic cover that helps keep moisture away from the center conductor. This makes thick coaxial a great choice when running longer lengths in a linear bus network. One disadvantage of thick coaxial is that it does not bend easily and is difficult to install.

Coaxial Cable Connectors

The most common type of connector used with coaxial cables is the Bayone-Neill-Concelman (BNC) connector (See fig. 4). Different types of adapters are available for BNC connectors, including a T-connector, barrel connector, and terminator. Connectors on the cable are the weakest points in any network. To help avoid problems with your network, always use the BNC connectors that crimp, rather screw, onto the cable.

Fig. 4. BNC connector

Fiber Optic Cable

Fiber optic cabling consists of a center glass core surrounded by several layers of protective materials (See fig. 5). It transmits light rather than electronic signals eliminating the problem of electrical interference. This makes it ideal for certain environments that contain a large amount of electrical interference. It has also made it the standard for connecting networks between buildings, due to its immunity to the effects of moisture and lighting.

Fiber optic cable has the ability to transmit signals over much longer distances than coaxial and twisted pair. It also has the capability to carry information at vastly greater speeds. This capacity broadens communication possibilities to include services such as video conferencing and interactive services. The cost of fiber optic cabling is comparable to copper cabling; however, it is more difficult to install and modify. 10BaseF refers to the specifications for fiber optic cable carrying Ethernet signals.

The center core of fiber cables is made from glass or plastic fibers (see fig 5). A plastic coating then cushions the fiber center, and kevlar fibers help to strengthen the cables and prevent breakage. The outer insulating jacket made of teflon or PVC.

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Fig. 5. Fiber optic cable

There are two common types of fiber cables -- single mode and multimode. Multimode cable has a larger diameter; however, both cables provide high bandwidth at high speeds. Single mode can provide more distance, but it is more expensive.

Specification Cable Type

10BaseT Unshielded Twisted Pair

10Base2 Thin Coaxial

10Base5 Thick Coaxial

100BaseT Unshielded Twisted Pair

100BaseFX Fiber Optic

100BaseBX Single mode Fiber

100BaseSX Multimode Fiber

1000BaseT Unshielded Twisted Pair

1000BaseFX Fiber Optic

1000BaseBX Single mode Fiber

1000BaseSX Multimode Fiber

Installing Cable - Some Guidelines

When running cable, it is best to follow a few simple rules:

Always use more cable than you need. Leave plenty of slack. Test every part of a network as you install it. Even if it is brand new, it may have

problems that will be difficult to isolate later. Stay at least 3 feet away from fluorescent light boxes and other sources of

electrical interference. If it is necessary to run cable across the floor, cover the cable with cable

protectors. Label both ends of each cable. Use cable ties (not tape) to keep cables in the same location together.

Wireless LANs

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More and more networks are operating without cables, in the wireless mode. Wireless LANs use high frequency radio signals, infrared light beams, or lasers to communicate between the workstations, servers, or hubs. Each workstation and file server on a wireless network has some sort of transceiver/antenna to send and receive the data. Information is relayed between transceivers as if they were physically connected. For longer distance, wireless communications can also take place through cellular telephone technology, microwave transmission, or by satellite.

Wireless networks are great for allowing laptop computers, portable devices, or remote computers to connect to the LAN. Wireless networks are also beneficial in older buildings where it may be difficult or impossible to install cables.

The two most common types of infrared communications used in schools are line-of-sight and scattered broadcast. Line-of-sight communication means that there must be an unblocked direct line between the workstation and the transceiver. If a person walks within the line-of-sight while there is a transmission, the information would need to be sent again. This kind of obstruction can slow down the wireless network. Scattered infrared communication is a broadcast of infrared transmissions sent out in multiple directions that bounces off walls and ceilings until it eventually hits the receiver. Networking communications with laser are virtually the same as line-of-sight infrared networks.

Wireless standards and speeds

The Wi-Fi Alliance is a global, non-profit organization that helps to ensure standards and interoperability for wireless networks, and wireless networks are often referred to as WiFi (Wireless Fidelity). The original Wi-Fi standard (IEEE 802.11) was adopted in 1997. Since then many variations have emerged (and will continue to emerge). Wi-Fi networks use the Ethernet protocol.

Standard Max Speed Typical Range

802.11a 54 Mbps 150 feet

802.11b 11 Mbps 300 feet

802.11g 54 Mbps 300 feet

802.11n 100 Mbps 300+ feet

Wireless Security

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Wireless networks are much more susceptible to unauthorized use than cabled networks. Wireless network devices use radio waves to communicate with each other. The greatest vulnerability to the network is that rogue machines can "eves-drop" on the radio wave communications. Unencrypted information transmitted can be monitored by a third-party, which, with the right tools (free to download), could quickly gain access to your entire network, steal valuable passwords to local servers and online services, alter or destroy data, and/or access personal and confidential information stored in your network servers. To minimize the possibility of this, all modern access points and devices have configuration options to encrypt transmissions. These encryption methodologies are still evolving, as are the tools used by malicious hackers, so always use the strongest encryption available in your access point and connecting devices.

A NOTE ON ENCRYPTION: As of this writing WEP (Wired Equivalent Privacy) encryption can be easily hacked with readily-available free tools which circulate the internet. WPA and WPA2 (WiFi Protected Access versions 1 and 2) are much better at protecting information, but using weak passwords or passphrases when enabling these encryptions may allow them to be easily hacked. If your network is running WEP, you must be very careful about your use of sensitive passwords or other data.

Three basic techniques are used to protect networks from unauthorized wireless use. Use any and all of these techniques when setting up your wireless access points:

Encryption. Enable the strongest encryption supported by the devices you will be connecting to the network. Use strong passwords (strong passwords are generally defined as passwords containing symbols, numbers, and mixed case letters, at least 14 characters long).

Isolation. Use a wireless router that places all wireless connections on a subnet independent of the primary private network. This protects your private network data from pass-through internet traffic.

Hidden SSID. Every access point has a Service Set IDentifier (SSID) that by default is broadcast to client devices so that the access point can be found. By disabling this feature, standard client connection software won't be able to "see" the access point. However, the eves-dropping programs discussed previously can easily find these access points, so this alone does little more than keep the access point name out of sight for casual wireless users.

Advantages of wireless networks:

Mobility - With a laptop computer or mobile device, access can be available throughout a school, at the mall, on an airplane, etc. More and more businesses are also offering free WiFi access ("Hot spots").

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Fast setup - If your computer has a wireless adapter, locating a wireless network can be as simple as clicking "Connect to a Network" -- in some cases, you will connect automatically to networks within range.

Cost - Setting up a wireless network can be much more cost effective than buying and installing cables.

Expandability - Adding new computers to a wireless network is as easy as turning the computer on (as long as you do not exceed the maximum number of devices).

Disadvantages of wireless networks:

Security - Be careful. Be vigilant. Protect your sensitive data with backups, isolated private networks, strong encryption and passwords, and monitor network access traffic to and from your wireless network.

Interference - Because wireless networks use radio signals and similar techniques for transmission, they are susceptible to interference from lights and electronic devices.

Inconsistent connections - How many times have you hears "Wait a minute, I just lost my connection?" Because of the interference caused by electrical devices and/or items blocking the path of transmission, wireless connections are not nearly as stable as those through a dedicated cable.

Speed - The transmission speed of wireless networks is improving; however, faster options (such as gigabit Ethernet) are available via cables. If you are only using wireless for internet access, the actual internet connection for your home or school is generally slower than the wireless network devices, so that connection is the bottleneck. If you are also moving large amounts of data around a private network, a cabled connection will enable that work to proceed much faster.

TYPES AND CONFIGURATION OF CABLES

Straight through

A network cabling that connects a computer to a network device. For example,straight through cables connect a computer to a network hub, network switch, and network routers. These are the standard network cables you would find at the store unless labelled as a cross-over cable. Straight-Through refers to cables that have the pin assignments on each end of the cable. In other words Pin 1 connector A goes to Pin 1 on connector B, Pin 2 to Pin 2 ect. Straight-Through wired cables are most commonly used to connect a host to client. When we talk about cat5e patch cables, the Straight-Through wired cat5e patch cable is used to connect computers, printers and other network client devices to the router switch or hub (the host device in this instance).

Connector A

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Pin 1 Pin 2 Pin 3 Pin 4 Pin 5 Pin 6 Pin 7 Pin 8

Connector B Pin 1 Pin 2 Pin 3 Pin 4 Pin 5 Pin 6 Pin 7 Pin 8

Crossover Wired Cables

Crossover wired cables (commonly called crossover cables) are very much like Straight-Through cables with the exception that TX and RX lines are crossed (they are at opposite positions on either end of the cable. Using the 568-B standard as an example below you will see that Pin 1 on connector A goes to Pin 3 on connector B. Pin 2 on connector A goes to Pin 6 on connector B ect. Crossover cables are most commonly used to connect two hosts directly. Examples would be connecting a computer directly to another computer, connecting a switch directly to another switch, or connecting a router to a router.Note: While in the past when connecting two host devices directly a crossover cable was required. Now days most devices have auto sensing technology that detects the cable and device and crosses pairs when needed.

Connector A Pin 1 Pin 2 Pin 3 Pin 4 Pin 5 Pin 6 Pin 7 Pin 8

Connector B

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Pin 3 Pin 6 Pin 1 Pin 7 Pin 8 Pin 2 Pin 4 Pin 5

Rollover Wired Cables Rollover wired cables most commonly called rollover cables, have opposite Pin assignments on each end of the cable or in other words it is "rolled over". Pin 1 of connector A would be connected to Pin 8 of connector B. Pin 2 of connector A would be connected to Pin 7 of connector B and so on. Rollover cables, sometimes referred to as Yost cables are most commonly used to connect to a devices console port to make programming changes to the device. Unlike crossover and straight-wired cables, rollover cables are not intended to carry data but instead create an interface with the device.

Connector A Pin 1 Pin 2 Pin 3 Pin 4 Pin 5 Pin 6 Pin 7 Pin 8

Connector B Pin 8 Pin 7 Pin 6 Pin 5 Pin 4 Pin 3 Pin 2 Pin 1

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IP ADDRESS FAMILIARIZATION

What is IP Address?

An Internet Protocol address (IP address) is a numerical label assigned to each device (e.g., computer, printer) participating in a computer network that uses the Internet Protocol for communication. An IP address serves two principal functions: host or network interface identification and location addressing. Its role has been characterized as follows: "A name indicates what we seek. An address indicates where it is. A route indicates how to get there."

The designers of the Internet Protocol defined an IP address as a 32-bit number[1] and this system, known as Internet Protocol Version 4 (IPv4), is still in use today. However, due to the enormous growth of the Internet and the predicted depletion of available addresses, a new version of IP (IPv6), using 128 bits for the address, was developed in 1995.IPv6 was standardized as RFC 2460 in 1998 and its deployment has been ongoing since the mid-2000s.

IP addresses are binary numbers, but they are usually stored in text files and displayed in human-readable notations, such as 172.16.254.1 (for IPv4), and 2001:db8:0:1234:0:567:8:1 (for IPv6).

The Internet Assigned Numbers Authority (IANA) manages the IP address space allocations globally and delegates five regional Internet registries (RIRs) to allocate IP address blocks to local Internet registries (Internet service providers) and other entities.

Two versions of the Internet Protocol (IP) are in use: IP Version 4 and IP Version 6.

Each version defines an IP address differently. Because of its prevalence, the generic

term IP address typically still refers to the addresses defined by IPv4. The gap in

version sequence between IPv4 and IPv6 resulted from the assignment of number 5 to

the experimentalInternet Stream Protocol in 1979, which however was never referred to

as IPv5.

IPv4 addresses

In IPv4 an address consists of 32 bits which

limits the address

space to 4294967296 (232) possible unique

addresses. IPv4 reserves some addresses

for special purposes such as private

networks (~18 million addresses)

or multicast addresses(~270 million

addresses).

IPv4 addresses are canonically represented in dot-decimal notation, which consists of

four decimal numbers, each ranging from 0 to 255, separated by dots, e.g.,

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172.16.254.1. Each part represents a group of 8 bits (octet) of the address. In some

cases of technical writing, IPv4 addresses may be presented in

various hexadecimal, octal, or binary representations.

IPv6 private addresses

Just as IPv4 reserves addresses for private or internal networks, blocks of addresses

are set aside in IPv6 for private addresses. In IPv6, these are referred to as unique local

addresses (ULA). RFC 4193 sets aside the routing prefix fc00::/7 for this block which is

divided into two /8 blocks with different implied policies. The addresses include a 40-bit

pseudorandom number that minimizes the risk of address collisions if sites merge or

packets are misrouted

Early designs used a different block for this purpose (fec0::), dubbed site-local

addresses. However, the definition of what constituted sites remained unclear and the

poorly defined addressing policy created ambiguities for routing. This address range

specification was abandoned and must not be used in new systems.

Addresses starting with fe80:, called link-local addresses, are assigned to interfaces for

communication on the link only. The addresses are automatically generated by the

operating system for each network interface. This provides instant and automatic

network connectivity for any IPv6 host and means that if several hosts connect to a

common hub or switch, they have a communication path via their link-local IPv6

address. This feature is used in the lower layers of IPv6 network administration

(e.g. Neighbor Discovery Protocol).

None of the private address prefixes may be routed on the public Internet.

IP address classes

Class 1st Octet Decimal Range

1st Octet High

Order Bits

Network/Host ID (N=Network,

H=Host)

Default Subnet Mask

Number of Networks

Hosts per Network (Usable

Addresses)

A 1 – 126* 0 N.H.H.H 255.0.0.0 126 (27 –

2) 16,777,214

(224 – 2)

B 128 – 191 10 N.N.H.H 255.255.0.0 16,382

(214 – 2) 65,534 (216 –

2)

C 192 – 223 110 N.N.N.H 255.255.255.0 2,097,150 (221 – 2)

254 (28 – 2)

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D 224 – 239 1110 Reserved for Multicasting

E 240 – 254 1111 Experimental; used for research

Note: Class A addresses 127.0.0.0 to 127.255.255.255 cannot be used and is reserved for loopback and diagnostic functions.

Private IP Addresses

Class Private Networks Subnet Mask Address Range

A 10.0.0.0 255.0.0.0 10.0.0.0 - 10.255.255.255

B 172.16.0.0 - 172.31.0.0 255.240.0.0 172.16.0.0 - 172.31.255.255

C 192.168.0.0 255.255.0.0 192.168.0.0 - 192.168.255.255

SETTING UP IP ADDRESS

Setting up a static ip for Windows 7.

If you have a printer, before you begin print out this page!

Step 1: Open up the start menu, and look for the Search programs and files box. You should now see the following window.

Step 2: Type cmd in the Search programs and files box, and press Enter on your keyboard. The will bring up a black command prompt window.

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Step 3: The command prompt may look different on your screen, but it doesn't really matter. Type ipconfig /all in that window, and then press the enter key. This will display a lot of information. If it scrolls off the top you may need to enlarge the window.

Step 4: I want you to write down some of the information in this window. Take down the IP address, Subnet Mask, Default Gateway, and Name Servers. Make sure to note which is which. We are going to use this information a little bit later. We are only concerned with IPv4 entries, you can ignore the IPv6 stuff.

The name server entries are a bit complicated. Name Server is just another name for DNS(domain name server) server. Some router's act as a proxy between the actual name servers and your computer. You will know when this is the case, because the Default Gateway will list the same ip address as the Name Servers entry. We need to have the correct Name Server IP addresses. If we do not, you will not be able to browse the web. There are a couple ways to get these. The first way is to log into your router's web interface, and look at your router's status page. On that page you should see an entry for DNS Servers, or Name Servers. Write down the ip adresses of your Name Servers. Another way to get the correct Name Servers to use, is to give your ISP a call. They should know the ip addresses of your Name Servers right off. If they ask you why you need them, you can tell them you are trying to setup a static IP address on your computer. If they try to sell you a static external ip address, don't buy it. That's an entirely different thing that what you are trying to setup.

Type exit in this window, then press the enter key to close it.

Step 5: Once again open the start menu. This time click Control Panel.

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Step 6: Click on View Network Status and Tasks.

Step 7:Single click Change adapter settings on the left side of your screen.

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Step 8: You might have more than one Internet connection listed here. You will need to determine which adapter is your connection to the Internet if this is the case. Right click on your network adapter and choose properties to open up the properties window of this internet connection.

Step 9: Click Internet Protocol Version 4(TCP/IPv4) and then the Properties button.

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You will see the following screen:

Step 10: Before you make any changes, write down the settings that you see on this page. If something goes wrong you can always change the settings back to what they

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were! You should see a dot in the Obtain an IP address automatically box. If you do not, your connection is already setup for a static ip. Just close all these windows and you are done.

Pick an ip address and enter it into the IP Address box. The ip address you choose should be very similar to the router's ip address. Only the last number of the ip address should be different. If the router's ip address is 192.168.1.1, I might choose 192.168.1.10. The ip address you choose should end with a number between 1 and 254, and should not be the same as the router's ip address. Every device that connects to your network needs to have it's own ip address.

Put the subnet mask we previously found in the subnet mask section. The default gateway should go into the Default gateway box. Enter the dns servers we previously found into the two DNS Server boxes. Click okay all the way out of this menu.

If you find that you can not pull up webpages, the problem is most likely the dns numbers you entered. Give your ISP a call, and they will be able to tell you which dns servers to use. This is a question they answer all of the time. They will be able to tell you what you should use right away.

That's it you should be done! If you can't connect to the internet go back and change your configuration back to what it originally was.

IP CONFIGURATION

Companies with advanced network configurations can configure multiple IP addresses

on the appliance’s Ethernet ports. Using multiple ports can enhance security or enable

connections over non-standard networks. For example, if employees are restricted from

accessing the Internet but need to provide off-network support, using one port for your

internal private network and another for the public internet would allow world-wide users

to request support without breaching your network security policies. The MTU can also

be configured per Ethernet port.

AUTOMATIC IP CONFIGURATION

Configuring your computer to obtain an IP address automatically allows your networking device to assign a dynamic IP address to it. Instead of manually entering the IP settings, which is time consuming, performing this procedure will ensure that the computer will get the correct TCP/IP settings. This process is useful when:

• Connecting a computer to a network with a DHCP server

• Ensuring that the computer is getting the correct TCP/IP settings

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To configure a computer to automatically get an IP address, you have to check the TCP/IP properties of the Ethernet adapter installed on the computer. You will not be able to check or configure the TCP/IP protocols on your computer if anEthernet Network Interface Card (NIC) is not installed on your computer. If you are using a wired connection, make sure that the computer is properly connected to a network with a DHCP server.

For instructions, follow the steps below:

Windows 7/Vista

Windows XP

Mac® OS

NOTE: If you have a Windows 8 and Windows 8.1 operating systems, click here for instructions. Windows Vista / 7

Step 1: Click the Pearl button then click Control Panel.

Step 2: Under the Network and Internet section, click View network status and tasks.

QUICK TIP: At the upper right hand of the Control Panel window, you may change the window’s view type by selecting Large icons or Small icons. Once you changed the view type, you can click on the Network and Sharing Centerinstead. In this example, we selected Small icons.

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Step 3: On the Network and Sharing Center window, click Change adapter settings.

NOTE: For Windows Vista, click Manage network connections.

Step 4: Right-click Local Area Connection, then click Properties.

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NOTE: For wireless computers, select Wireless Network Connection instead then click Properties.

Step 5: On the Local Area Connection Properties window, select Internet Protocol Version 4 (TCP/IPv4) then click Properties.

Step 6: Select Obtain an IP address automatically and Obtain DNS server address automatically.

Step 7: Click OK to save the changes.

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NOTE: If the computer did not obtain an IP address, renew the IP address. For instructions, click here.

Windows XP

Step 1: Click Start > Control Panel.

Step 2: On the Control Panel window, double-click Network Connections. QUICK TIP: Check the upper left corner of the Control Panel screen. Click Switch to

Classic View to easily locate the Network Connections icon.

Step 3: Right-click Local Area Connection then click Properties.

NOTE: For

wireless computers, select Wireless Network Connection instead then click Properties. Step 4: On the Local Area Connection Properties window, select Internet Protocol (TCP/IP). Then click Properties.

Step 5: Make sure that the Obtain an IP address automatically and Obtain DNS server address automatically radio buttons are selected.

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Step 6: Click OK to save the changes.

NOTE: If the computer did not obtain an IP address, renew the IP address. For instructions, click here.

Mac® OS

Step 1: Click the Apple icon then select the System Preferences... option.

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Step 2: On the System Preferences window, click Network.

Step 3: On the Network window, look for the Show field and make sure that Built-in Ethernet is selected.

NOTE: For wireless computers, select Airport instead. For higher versions, select Ethernet on the left panel.

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Step 4: Under the TCP/IP tab, look for Configure IPv4 and make sure Using DHCP is selected.

NOTE: In this example, 192.168.1.100 is

used as the IP address that the Mac is automatically getting from the DHCP server.

Step 5: Click if you made any changes.

NOTE: If the computer did not obtain an IP address, renew the IP address. For instructions, click here.

MANUAL ALLOCATION OF IP ADDRESS

This option requires technicians or support staff to manually configure IP addresses and related settings, such as subnet masks, default gateways, and DNS suffixes on

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computers and network devices. In the case of Windows operating systems, this requires editing properties of the network connection. In other operating systems, configuration can involve the creation or modification of configuration files. Depending on the type of device, it might be possible to automate this process. For example, when deploying Windows-based computers, IP address information can be included in unattended information files used during automatic software builds.

In addition to the address configuration task, it is essential to have a clear plan and documentation system in place to ensure that the correct addresses are used and the same addresses are not allocated more than once. Many devices, including Windows-based computers, report a failure and refuse to bind an IP address if an Address Resolution Protocol discovery shows that it is already bound to another device.

Advantages

The advantages of manually configured IP addresses include:

Simple approach: This option is the simplest approach to understand and is not dependent on any other technology or service. If the correct IP address configuration information is used, the device will have a functional IP stack and will be able to communicate on the network.

Fixed and predictable: Manually configured addresses are fixed and therefore predictable. Allocating addresses from central servers can result in changes to the address or to its associated IP information; if these changes are not anticipated, there can be network problems.

Disadvantages

The disadvantages of manually configured IP addresses include:

High overhead: Using manual configuration to maintain all IP addresses across an enterprise network would generate excessive overhead expense. There would also be a great risk of errors and incorrect configurations due to the numbers of addresses that need to be managed. However, this approach is feasible if the network is small or if manual configuration is used only in parts of a larger network.

Risk of wasting addresses: Manually configured addressing can lead to the waste of IP addresses. Devices with an assigned address might be decommissioned but the IP address cannot be reused without some means of reclaiming those no longer in use.

Mobile device reconfiguration: Devices moved from one part of the network to another must be reconfigured for proper network operation. For mobile computing devices, such as laptop computers or PDAs, such reconfiguration becomes time-consuming; it is an impediment to efficient business operations.

Windows 7: Alternate IP Address Configuration

Laptop computers often have to connect to multiple network (e.g. home, office, retail,

etc.). In the past If one of the networks required a static IP address, while the other

networks assigned addresses via DHCP you had to manually change the TCP/IP

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properties every time you switched networks. Since Windows Vista, you now have

the ability to setup an alternate IP address configuration.

In the Start menu search field, type Network Connections and select View network connections.

In the Network Connections window, right-click a connection that needs an alternate IP address configuration (e.g., Local Area Connection) and select Properties.

In the Properties dialog box, on the Networking tab, scroll down and click Internet Protocol Version 4 (TCP/IP v4) and press the Properties button.

In the General tab, enter the information for the main network you use (such as a static IP, subnet mask, default gateway and DNS server information).

Click the Alternate Configuration tab, then click Automatic Private IP Address so the computer will obtain an IP address via DHCP.

Press OK button twice to close the dialog boxes.

COMPUTER NETWORK

Introduction

Basic of Networking A computer network consists of a collection of computers, printers and other equipment that is connected together so that they can communicate with each other. Fig 1 gives an example of a network in a school comprising of a local area network or LAN connecting computers with each other, the internet, and various servers. Peer-to-peer networks Are more commonly implemented where less then ten computers are involved and where strict security is not necessary. All computers have the same status, hence the term 'peer', and they communicate with each other on an equal footing. Files, such as word processing or spreadsheet documents, can be shared across the network and all the computers on the network can share devices, such as printers or scanners, which are connected to any one computer.

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Client/server networks Client/server networks are more suitable for larger networks. A central computer, or 'server', acts as the storage location for files and applications shared on the network. Usually the server is a higher than average performance computer. The server also controls the network access of the other computers which are referred to as the 'client' computers. Typically, teachers and students in a school will use the client computers for their work and only the network administrator (usually a designated staff member) will have access rights to

the server. Table 1 provides a summary comparison between Peer-to-Peer and Client/Server Networks.

Peer-to-Peer Networks vs Client/Server Networks

Peer-to-Peer Networks Client/Server Networks

Easy to set up More difficult to set up

Less expensive to install More expensive to install

Can be implemented on a wide range of operating systems

A variety of operating systems can be supported on the client computers, but the server needs to run an operating system that supports networking

More time consuming to maintain the software being used (as computers must be managed individually)

Less time consuming to maintain the software being used (as most of the maintenance is managed from the server)

Very low levels of security supported or none at all. These can be very cumber some to set up, depending on the operating system being used

High levels of security are supported, all of which are controlled from the server. Such measures prevent the deletion of essential system files or the changing of settings

Ideal for networks with less than 10 computers

No limit to the number of computers that can be supported by the network

Does not require a server Requires a server running a server operating system

Demands a moderate level of skill to administer the network

Demands that the network administrator has a high level of IT skills with a good working knowledge of a server operating system

Table 1: Peer-to-Peer Networks vs Client/Server Networks

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NETWORK TROUBLESHOOTING

Top 10 Basic Network Troubleshooting Tools Every IT Pro Should Know

Network troubleshooting tools are a necessity for every network administrator. When getting started in the networking field, it is important to amass a number of tools that can be used to troubleshoot a variety of different network conditions.

While it is true that the the use of specific tools can be subjective and at the discretion of the engineer, the selection of tools in this article has been made based on their generality and common use. This article reviews the top 10 basic tools that can help you troubleshoot most networking issues.

10. Ping

The most commonly used network tool is the ping utility. This utility is used to provide a basic connectivity test between the requesting host and a destination host. This is done by using the Internet Control Message Protocol (ICMP) which has the ability to send an echo packet to a destination host and a mechanism to listen for a response from this host. Simply stated, if the requesting host receives a response from the destination host, this host is reachable. This utility is commonly used to provide a basic picture of where a specific networking problem may exist. For example, if an Internet connection is down at an office, the ping utility can be used to figure out whether the

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problem exists within the office or within the network of the Internet provider. Figure 1 below shows an example of the ping utility being used to obtain the reachability status of the locally connected router.

9. Tracert/traceroute

Typically, once the ping utility has been used to determine basic connectivity, the tracert/traceroute utility can used to determine more specific information about the path to the destination host including the route the packet takes and the response time of these intermediate hosts. Figure 2 below shows an example of the tracert utility being used to find the path from a host inside an office to www.google.com. The tracert utility and traceroute utilities perform the same function but operate on different operating systems, Tracert for Windows machines and traceroute for Linux/*nix based machines.

8. Ipconfig/ifconfig

One of the most important things that must be completed when troubleshooting a networking issue is to find out the specific IP configuration of the variously affected hosts. Sometimes this information is already known when addressing is configured statically, but when a dynamic addressing method is used, the IP address of each host can potentially change often. The utilities that can be used to find out this IP configuration information include the ipconfig utility on Windows machines and the ifconfig utility on Linux/*nix based machines. Figure 3 below shows an example of the ifconfig utility showing the IP configuration information of a queries host.

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7. Nslookup

Some of the most common networking issues revolve around issues with Dynamic Name System (DNS) address resolution issues. DNS is used by everyone using the Internet to resolve commonly known domain names (i.e. google.com) to commonly unknown IP addresses (i.e. 74.125.115.147). When this system does not work, most of the functionality that people are used to goes away, as there is no way to resolve this information. The nslookup utility can be used to lookup the specific IP address(es) associated with a domain name. If this utility is unable to resolve this information, there is a DNS issue. Along with simple lookup, the nslookup utility is able to query specific DNS servers to determine an issue with the default DNS servers configured on a host. Figure 4 below shows an example of how the nslookup utility can be used to query the associated IP address information.

Figure 4: Nslookup utility

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6. Netstat

Often, one of the things that are required to be figured out is the current state of the active network connections on a host. This is very important information to find for a variety of reasons. For example, when verifying the status of a listening port on a host or to check and see what remote hosts are connected to a local host on a specific port. It is also possible to use the netstat utility to determine which services on a host that is associated with specific active ports. Figure 5 below shows an example of the netstat utility being used to display the currently active ports on a Linux machine.

5. PuTTY/Tera Term

When connecting to a variety of different types of equipment, a telnet, SSH or serial client is required; when this is required both the puTTY and Tera Term programs are able to provide these functionalities. The selection of one over the other is strictly a personal preference. Figures 6 and 7 below show both puTTY and Tera Term being used to connect to a host via SSH.

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4. Subnet and IP Calculator

One of the most important tools in the belt of a junior network engineer is an IP network calculator. These can be used to unsure a correct IP address selection and with this a correct IP address configuration. While this type of tool is used by senior level network engineers, much of the information obtained from the tool becomes simpler to calculate the longer and more experience you have in the field. Two of the more commonly used free IP calculators include Wildpackets (Bitcricket) Network Calculator and Solarwinds Advanced Subnet Calculator which can be found at the links below.

3. Speedtest.net/pingtest.net

A very easy test that can be used to both determine the Internet bandwidth available to a specific host and to determine the quality of an Internet connection is the use of the tools available at the speedtest.net and pingtest.net websites. The speedtest.net site provides the ability to determine the amount of bandwidth that is available to a specific host at a specific point in time; this is often a good tool to use when measuring how long it is going to take to upload or download information from a local to remote host. This measurement can also be used to determine whether the connection is offering the

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amount of bandwidth that was purchased from the Internet provider; keep in mind however that some amount of bandwidth difference is expected between the quoted bandwidth purchased and the measured bandwidth. The pingtest.net website is used to determine the quality of the connection by measuring the ping response times and jitter amounts over a short period of time. This information can be used to determine a likelihood of how well the measured connection will deal with certain types of high demand traffic like Voice over IP (VoIP) or gaming. Figure 9 and 10 below show example output from both of these sites.

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2. Pathping/mtr

In an effort to take advantage of the benefits of both the ping and tracert/traceroute commands, the pathping and mtr utilities were developed. Both of these tools take the functionality and information that can be obtained from these types of tools and provide a more detailed single picture of the path characteristics from a specific host to a specific destination. Figure 11 and 12 below show examples of these two tools and what information they provide.

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1. Route

The last of the tools covered in this article is the route utility. This utility is used to display the current status of the routing table on a host. While the use of the route utility is limited in common situations where the host only has a single IP address with a single gateway, it is vital in other situations where multiple IP address and multiple gateways are available. Figure 13 below shows an example of the route utility being used on a Windows machine.

Figure 13: Route Utility

Summary

As with any job, the type of tools that are quickly available can greatly influence the amount of time that it takes to complete a job. When troubleshooting a networking issue, the amount of time that it takes to find and fix a problem directly affect the wasted costs that it causes to any system relying on the network. This article has taken a look at the 10 most commonly used tools that can help in ensuring that the time that it takes

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to find and fix a problem is as short as possible. I hope the information in this article can be helpful in future troubleshooting.

TESTING DEVICES

1. LAN TESTER / Cable Tester

A cable tester is an electronic device used to verify the

electrical connections in a cable or other wired assembly.

Generally a cable tester consists of:

1. A source of electric current,

2. A volt meter,

3. A switching matrix used to connect the current

source and the volt meter to all of the contact points in a

cable.

In addition to these parts a cable tester may also have a

microcontroller and a display to automate the testing

process and show the testing results.

A cable tester is used to verify that all of the intended connections exist and that there

are no unintended connections in the cable being tested. When an intended connection

is missing it is said to be "open". When an unintended connection exists it is said to be a

"short" (as in short circuit). If a connection "goes to the wrong place" it is said to be

"miswired" (the connection has two faults: it is open to the correct contact and shorted

to an incorrect contact).

Generally, the testing is done in two phases. The first phase, called the opens

test makes sure each of the intended connections is good. The second phase, called

the shorts test makes sure there are no unintended connections.

There are two common ways to test a connection:

1. A continuity test. Current is passed down the connection. If there is current the

connection is assumed to be good. This type of test can be done with a series

combination of a battery (to provide the current) and a light bulb (that lights when

there is a current).

2. A resistance test. A known current is passed down the connection and the

voltage that develops is measured. From the voltage and current the resistance

of the connection can be calculated and compared to the expected value.

There are two common ways to test for a short:

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1. A low voltage test. A low power, low voltage source is connected between two

conductors that should not be connected and the amount of current is measured.

If there is no current the conductors are assumed to be well isolated.

2. A high voltage test. Again a voltage source is connected but this time the voltage is of several hundred volts. The increased voltage will make the test more likely to find connections that are nearly shorted since the higher voltage will cause the insulation of nearly shorted wires to break down.

2. PING COMMANDS

What is the Ping Command?

The ping command is a Command Prompt command used to test the ability of the

source computer to reach a specified destination computer. The ping command is

usually used as a simple way verify that a computer can communicate over the network

with another computer or network device.

The ping command operates by sending Internet Control Message Protocol (ICMP)

Echo Request messages to the destination computer and waiting for a response. How

many of those responses are returned, and how long it takes for them to return, are the

two major pieces of information that the ping command provides.

Using the ping command

If you are having connectivity problems, you can use the ping command to check the

destination IP address you want to reach and record the results. The ping command

displays whether the destination responded and how long it took to receive a reply. If

there is an error in the delivery to the destination, the ping command displays an error

message.

You can use the ping command to:

Ping your computer (by address, not host name) to determine that TCP/IP is

functioning. (Pinging your computer does not verify that your network adapter is

functioning.)

Ping the local router to determine whether the router is running.

Ping beyond your local router.

The following table shows some useful ping command options.

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Option Use

-n Count Determines the number of echo requests to send. The default is 4 requests.

-w Timeout Enables you to adjust the time-out (in milliseconds). The default is 1,000 (a 1-second time-out).

-l Size Enables you to adjust the size of the ping packet. The default size is 32 bytes.

-f Sets the Do Not Fragment bit on the ping packet. By default, the ping packet allows fragmentation.

The following example illustrates how to send two pings, each 1,450 bytes in size, to IP

address 131.107.8.1:

C:\>ping -n 2 -l 1450 131.107.8.1

Pinging 131.107.8.1 with 1450 bytes of data:

Reply from 131.107.8.1: bytes=1450 time<10ms TTL=32

Reply from 131.107.8.1: bytes=1450 time<10ms TTL=32

Ping statistics for 131.107.8.1:

Packets: Sent = 2, Received = 2, Lost = 0 (0% loss),

Approximate roundtrip times in milliseconds:

Minimum = 0ms, Maximum = 10ms, Average = 2ms

By default, ping waits 4,000 milliseconds (4 seconds) for each response to be returned

before displaying the "Request Timed Out" message. If the remote system being pinged

is across a high-delay link, such as a satellite link, responses may take longer to be

returned. You can use the -w (wait) option to specify a longer time-out.

For more information about other ping options, see Command-line utilities.

To check connectivity by using the ping command, at the command prompt,

type ping and the IP address you want to reach.

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A response of "Destination net unreachable" means there was no route to the

destination. You need to check the routing table on the router listed in the "Reply from"

address in the "Destination net unreachable" message. For more information about the

routing table, see Understanding the IP routing table.

A response of "Request timed out" means that there was no response to the ping in the

default time period (1 second). You can check for the following:

A router is down.

To check the routers in the path between the source and the destination, use

the tracert command. For more information, see Using the tracert command.

The destination host is down.

Physically verify that the host is running or check connectivity through another protocol.

There is no route back to your computer.

If the host is running, you can check for a return route by viewing the default gateway and local routing table on the destination host.

The latency of the response is more than one second. Use the -w option on the ping command to increase the time-out. For example, to

allow responses within 5 seconds, use ping -w 5000.

SYMPTOMS AND DIAGNOSIS

Troubleshooting Your Network Connection

Below are some common problems our users have experienced trying to connect

computers to the Caltech network, and their symptoms.

The ping program is very helpful in diagnosing network problems. Basically, it sends a

little greeting which is network language for "hello, how's it going?" and then expects for

a little confirmation back of "fine, thanks!". If you have never used ping before, IMSS

staffers are happy to help you learn how to use it.

Problem: Server Problems at your Destination

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Symptoms: Your computer can reach everything else except a particular server,

which of course is the one you need to get to. For instance, if you're trying to get

to http://www.google.com/ and cannot, but can get everywhere else on the web,

the problem is very likely that Google is having problems at their end.

Solution: You can try sending in a trouble report to the administrators of the

destination site, though they likely know already that there are problems. Your

only other recourse is to take a deep breath and do something else until their

server(s) come back online. If you know of a similar site or server to the one you

cannot reach, you could also try that (for instance, using Yahoo rather than

Google).

If you are having difficulty reaching a specific server at Caltech, but do not know

how to contact the administrators of it, IMSS may be able to assist you in reaching

them. Submit a request at http://help.caltech.edu (request type IMSS--

>Other) briefly describing your situation and request the contact information for the

administrators of the Caltech system you are trying to reach.

Problem: Bad Subnet Mask in Configuration

Symptoms: Cannot successfully ping computers on your same subnet (for

example, your default router's IP address), but can successfully ping computers of

your same subnet (for example, 131.215.48.254).

Solution: Doublecheck your computer's IP address configuration, according to the

configuration guides by operating system link in the Campus Network Services

section of this website, paying specific attention to the subnet mask in your

configuration. That should correct the problem. If not, see below.

Problem: Bad Default Route

Symptoms: Can successfully ping computers on your same subnet (for example,

your default router's IP address), but cannot successfully ping computers of your

same subnet (for example, 131.215.48.254).

Solution: Doublecheck your computer's IP address configuration, according to the

configuration guides by operating system link in the Campus Network Services

section of this website. That should correct the problem. If not, see below.

Problem: Bad DNS Servers (Or None) in Configuration

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Symptoms: Can successfully ping computers by IP address, but cannot ping

computers by name (for example, its.caltech.edu).

Solutions: Doublecheck your computer's IP address configuration, according to

the configuration guides by operating system link in the Campus Network Services

section of this website, paying specific attention to the DNS servers listed in your

configuration. That should correct the problem. If not, see below.

Problem: Bad IP Address in Configuration

Symptoms: Cannot ping anything successfully.

Solution: Doublecheck your computer's IP address configuration, according to the

configuration guides by operating system link in the Campus Network Services

section of this website, paying specific attention to the IP address assigned to your

computer. That should correct the problem. If not, see below.

Problem: Network Access Blocked For Computing Security Reasons

Symptoms: Network access that used to work suddenly stops working. Can no

longer access Caltech servers or off-campus systems. May or may not appear to

have an IP address.

Solution: Check to see if your computer has been blocked from accessing the

network, by entering your system's MAC address at the MAC Address Block

Check webpage.

If your computer was indeed blocked, contact us at http://help.caltech.edu(request

type IMSS-->Information Security-->Other). Consider registering as the contact for

your computer by its MAC address at the MAC Registry webpage this way you will

be contacted if there's a problem in the future.

Problem: Bad Hardware (Network Interface Card, Cabling, Wall Port, Wall Wiring, etc.)

Symptoms: Cannot ping anything successfully.

Solution: Double check your computer's IP address configuration, according to the

guides by operating system to be certain that a misconfiguration is not the cause

of your problem. Submit a request at http://help.caltech.edu (request type IMSS--

>Network, WIreless & Remote Access-->Other) with your exact location, your

computer's operating system, your computer's MAC Address, whether you are

using DHCP or a Static IP Address, the IP address you are using, and list what

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you have already double checked. We will arrange for a network engineer to test

the connection to your wall port, and from there, narrow down if the problem is

with our equipment, your cabling, or your network interface card.

If you are unable to send email, call the IMSS Help Desk at 626.395.3500 and ask

the Help Desk representative to open a ticket with our Network group, being sure

to provide all of the above details.

Other Problems:

If you have looked over this list and are still stumped, please submit a request

at athttp://help.caltech.edu (request type IMSS-->Network, WIreless & Remote

Access-->Other) with your exact location, your computer's operating system, your

computer's MAC Address, whether you are using DHCP or a Static IP Address,

the IP address you are using, and list everything which you have already double

checked in detail.

If you are unable to send email, call the IMSS Help Desk at 626.395.3500 and ask

the Help Desk representative to open a ticket with our Network group, being sure

to provide all of those details. We're happy to help get you back on the Caltech

network.

Basic network troubleshooting

Because of the variety of network configurations, operating systems, setup, etc. not all

of the below information may apply to your network or operating system.

Note: We cannot assist you with network problems due to an unknown passwords

or unknown ISP settings. Since we have no method of verifying or determining this

information.

Adapter resources

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Verify that the network adapter is properly installed and detected by the computer

with no conflicts. If you're using Microsoft Windows check in Device Manager and

verify there are no errors and "Network adapters" is present with each network

adapter installed in the computer listed, similar to the example on the right.

How do I get into Windows Device Manager?

Identifying problems in Windows Device Manager.

If conflicts exist or the network adapter is being detected as an Other device. The

network card has not been properly installed in the computer. Try letting Windows

re-detect and install the Network card by removing the network adapter and any

other conflict devices from Device Manager and then rebooting the computer. If

Windows re-detects the card but does not find the drivers, download the network

adapter drivers from the computer manufacturer or the network card

manufacturer.

Verify connections

Wired Network

If this is a wired network, verify that the network cable

is properly connected and make sure the LEDs next to the network jack are

properly illuminated. For example, a network card with a solid green LED or light

usually indicates that the card is either connected or receiving a signal. If the

green light is flashing, this is an indication of data being sent or received. In the

picture is an example of LAN port with two LED indicators next to the RJ-45 port.

With this port, one LED will light up if connected properly and the other will flash

when transmitting data.

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If there are no lights or the lights are orange or red the card may be bad, not

connected properly, or that the card is not receiving a signal from the network. If

you are on a small or local network and have the capability of checking

a hub, switch, orrouter verify that the cables are properly connected and that it has

power. If after checking the connections the LED indicators appear bad, the

network adapter, port, or cable may be defective.

Wireless Network

If you're using a laptop with a wireless network

make sure if the laptop has a Wi-Fi button that it is turned on. Many laptops have

a Wi-Fi button that allows the wireless network to be turned on and off. In the

picture is an example of a Wi-Fi button that is currently enabled.

If the Wi-Fi button is turned on, make sure you're connecting to the correct Wi-

Fi hotspot by right-clicking on the Network icon in the Windows notification

area and clicking "Connect to a network". Usually, the network with the strongest

connection (the most bars) will be your wireless router.

Finally, when connecting to most wireless networks you need to enter the

proper SSID(password) in order to connect to the network. If the incorrect SSID

has been entered you cannot access the network.

Adapter functionality

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Verify that the network card is capable of pinging itself by using the ping

command. Windows users can ping the computer from a Windows command line.

Unix and Linux users can ping from the shell.

To ping the card or the localhost, type either

ping 127.0.0.1

or

ping localhost

Doing either of the above commands should get replies from the network card. If

you receive an error or if the transmission fails the network card is not physically

installed into the computer correctly, has the incorrect drivers, or that the card is

bad.

Connect to the router

If all of the above steps have been checked and your network has a router, make

sure the computer can connect to the router by performing the below commands.

Determine the routers address

Using the ipconfig command (or ifconfig command for Linux) determine the

router's address by looking at the Gateway address. Below are the steps for

Microsoft Windows users, Linux users can substitute ipconfig for ifconfig.

1. Open the Windows command line.

2. From the command prompt type ipconfig and press enter. This command

should give you an output similar to the example below.

Ethernet adapter Local Area Connection:

Connection-specific DNS Suffix . : computerhope.com.

IP Address. . . . . . . . . . . . : 192.168.1.103

Subnet Mask . . . . . . . . . . . : 255.255.255.0

Default Gateway . . . . . . . . . : 192.168.1.1

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The Default Gateway is the address of your router. Most home routers have a

gateway address that starts with 192.168 like the address shown above.

Assuming your gateway address is 192.168.1.1 attempt to ping the router to see if

it can send and receive information by running the below command.

ping 192.168.1.1

If you get replies back from the router, the connection between your router and

computer are good, and you can skip to the next step.

If you do not receive any replies back from the router either the router is not setup

properly or your connection between the router and the computer are not correct.

Reset your router to make sure it is not a problem with your router by following the

steps below.

1. Turn off the power to the computer and leave it off.

2. Unplug the power to your router and cable modem or DSL modem.

3. Leave the power cables disconnected for 10-15 seconds and then plug in

your modem and then your router again.

4. Finally, turn on your computer again and repeat this step to see if you can

ping your router.

If you're using a wireless network and have followed all the above steps and still

are unable to ping the router try turning off the computer again and connect the

computer to the router using a cable instead of trying to connect using wireless. If

a wire does also not work connect the manufacturer of the router for additional

support or replacement.

Firewall

If your computer network utilizes a firewall, make sure all required ports required

are open, especially port 80, which is the HTTP port. If possible, disable the

firewall software program or disconnect the computer from the firewall to make

sure it is not causing the network problems.

Internet is not working

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If you're able to ping the router, but are still unable to connect to the Internet,

either your router is improperly configured or the ISP is having issues.

Note: Some ISPs such as Comcast require special software be installed. Make

sure any software included with your Modem or other hardware has been installed

on at least one computer if you are setting up a new Internet connection.

If your Internet has been working but recently stopped working, give it a few

minutes to make sure it is not a temporary outage. If after waiting a few minutes,

you still have problems and you have not disconnected the power to your router

and modem already follow the steps below.

1. Turn off the power to the computer and leave it off.

2. Unplug the power to your router and cable modem or DSL modem.

3. Leave the power cables disconnected for 10-15 seconds and then plug in

your modem and then your router again.

4. Finally, turn on your computer again and repeat this step to see if you can

ping your router.

If after following the above steps the Internet is still not working, open the

Windows command line and run the below command.

ping google.com

Running the above command should get a reply from Google. If you get a reply,

this is an indication that the Internet is working, but you may be encountering a

problem with the Internet browser you are using to browse the Internet. Try an

alternative browser such as Firefox or Chrome.

If you're getting no reply from Google, your router or modem is not reaching the

Internet. If you have a router, make sure your router has DHCP enabled and that

theWAN or Gateway address is the proper ISP address.

Finally, after verifying all of the above settings if your Internet is still not working

we suggest contacting the ISP to make sure it is not a problem on their end and to

assist you further with any special configurations that may not be mentioned in this

document.

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Additional troubleshooting

Another method of determining network issues is to use the tracert command if

you are a Windows user or the traceroute command if you are a Linux or Unix

variant user. This command gives you an overview of each of the devices

(routers) a packet travels (hops) over a network and can give you an idea of

where a problem exists in your network or outside of your network.

To use this command you must be at the command line and type one of the below

commands depending on your operating system.

tracert google.com

or

traceroute google.com

If run successfully you should begin to see each hop between the computer and

network devices. When the connection fails, determine what device is causing the

issue by reviewing the traceroute listing.

CHAPTER SUMMARY:

NETWORKING - A computer network consists of a collection of computers, printers and other equipment that is connected together so that they can communicate with each other. Types of Computer Network

SAN LAN MAN WAN

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Examples of NETWORKING DEVICES Modem Hub Switch Repeaters Router

Types of Network Topology Star Ring Bus Mesh Token ring

Cabling - there are three types of cables - Straight through, Crossover, Rollover

IP - stands for Internet Protocol Peer - Peer - implemented where less then ten computers are involved and where strict security is not necessary. Client /Server Network - A central computer, or 'server', acts as the storage location for files and applications shared on the network.

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CHAPTER QUIZ

1. What is the Importance of Computer Networking? 2. Differentiate the LAN and WAN? 3. What is Internet Protocol Address? Give an example. 4. What is cabling? 5. What is the difference between Peer to Peer Network and Client/ Server

Network? 6. 7. Types of Computer Network. 8. Describe each. 9. 10. 11. 12. 5 Network Devices and its uses. 13. 14. 15. 16. 17. 5 Network Topology and describe. 18. 19. 20. Give at least 1 type of cable, then Explain.

***Good Luck!***