INTRODUCTION TO COMPUTER TECHNOLOGY

F1031 - COMPUTER HARDWARE

COMPUTERS’ APPLICATIONS

Specifications based on the application:Home computersEntertainment / gaming computersMultimedia editing computersApplication server

Computer case (chassis)

CHASSIS ABCsThe computer case or chassis is the body

of the computer. Cases allow for manufacturers to include

all computer comments together and have it able to be moved, if needed.

Types of cases

Mini tower◦ Advantages:

Excellent size which can be placed on top or below of a computer desk.Disadvantages:While this case does offer upgradability, it can be filled up much faster than the Mid-Sized tower.Recommendations:Great PC for end-users and small businesses.

Types of cases

Mid-size tower◦ Advantages:

Excellent case which can fit below and on top of your computer desk.Plenty of expandability for new devices for businesses, end-users, and advanced users.One of the most used computer cases found today.Disadvantages:NoneRecommendations:This case is an excellent choice for all users and businesses.

Full size tower◦ Advantages:

Excellent computer for upgradability.Excellent case for a server machine.Disadvantages:Cost is going to be a lot more than a standard case.Generally a large case which cannot be placed on top or beneath a desk.Recommendations:We recommend that this type of case be purchased by advanced users or users who plan to have a stand alone machine as a server.

Types of cases

Desktop◦ Advantages:

Excellent desk computer.Great use of desk space when monitor is placed on top of the computer.Disadvantages:With some types of desktop cases can be very difficult to upgrade.Does not really work on the floor.Recommendations: Excellent choice for a business and home user computer. End users planning to upgrade or place computer on floor we recommend going with tower computer unless the manufacturer provides a desktop that can be converted to tower.

Types of cases

Slimline Desktop◦ Advantages:

Excellent for workstations in large companies.Great computer for a low budget PC.Excellent computer for locations which may not have large area of workspace.Disadvantages: Generally little or no room for adding additional peripherals.Usually require an LPX motherboard.Recommendations:We recommend that this type of case be purchased only for companies employees as workstations.

Types of cases

Definition:◦The monitor is a hardware device which

physically connects to video card. The monitor allows information and current status be visually outputted similar to a TV.

◦Two types of monitor: CRT LCD/TFT

Monitor

Types of monitor

CRT ◦ Cathode Ray Tube, ◦ The CRT is the main component and most expensive part within

computer monitor. ◦ Within the CRT are three electron guns, Red, Green and Blue. ◦ Each of these guns streams a steady flow of electrons, left to right, for

each line of monitor. ◦ As the electrons hit the phosphors on the CRT, the phosphor will glow

certain intensities. ◦ As a new line begins, the guns will then begin at the left and continue

right; these guns will repeat this process sometimes thousands of times until the screen has been completely drawn line by line.

◦ Once the phosphors on the CRT have been hit with an electron they will only glow for a short period of time; because of this, the CRT must be refreshed, which means the process will be repeated as explained above.

◦ If the video card's refresh rate is not set high enough, you may encounter a flicker or a noticeable steady line scrolling from the top to the bottom of the screen.

Types of monitor

CRT

MINIMUM RESOLUTION◦The size is an important factor of the

computer's running resolution. When picking the resolution, try basing it off the monitor's size for best use.

◦13-inch = 640 x 480 ◦15-inch = 800 x 600 ◦17-inch = 1,024 x 768 ◦21-inch = 1,280 x 1,024

Types of monitor

GHOST / BURN◦ If monitors, especially older CGA / EGA monitors,

are left on for long durations, the electron beams cause the phosphors to glow.

◦ If the electron guns continue to do this for thousands of hours refreshing the same images, this can cause the images to be burnt into the CRT surface causing a ghost image to appear.

◦This image will become permanently displayed on your monitor for the duration of its life.

◦A resolution to this problem are screen savers, which are programs that generate a random set of images, lines or other methods of allowing the image to not remain static while the computer is not being used.

Types of monitor

Advantages of CRT Monitors

Less expensive - Although LCD monitor prices have decreased, comparable CRT displays still cost less.

Better color representation - CRT displays have historically represented colors and different gradations of color more accurately than LCD displays. However, LCD displays are gaining ground in this area, especially with higher-end models that include color-calibration technology.

More responsive - Historically, CRT monitors have had fewer problems with ghosting and blurring because they redrew the screen image faster than LCD monitors. Again, LCD manufacturers are improving on this with displays that have faster response times than they did in the past.

Multiple resolutions - If you need to change your display's resolution for different applications, you are better off with a CRT monitor because LCD monitors don't handle multiple resolutions as well.

More rugged - Although they are bigger and heavier than LCD displays, CRT displays are also less fragile and harder to damage.

Defintion LCD/TFT◦A TFT monitor uses thin-film transistor

technology for the ultimate LCD display. LCD monitors, also called flat panel displays, are replacing the old style cathode ray tubes (CRTs) as the displays of choice. Nearly all LCD monitors today use TFT technology

Types of monitor

BenefitsThe benefit of a TFT monitor is

a separate, tiny transistor for each pixel on the display.

the amount of charge needed to control it is also small.

very fast re-drawing of the display, image is re-painted or refreshed several times

per second.

Types of monitor

Resolutions◦A typical 17-inch TFT monitor has about 1.3

million pixels and 1.3 million transistors.

Types of monitor

Advantages of LCD Monitors

Require less power - Power consumption varies greatly with different technologies. CRT displays are somewhat power-hungry, at about 100 watts for a typical 19-inch display. The average is about 45 watts for a 19-inch LCD display. LCDs also produce less heat.

Smaller and weigh less - An LCD monitor is significantly thinner and lighter than a CRT monitor, typically weighing less than half as much. In addition, you can mount an LCD on an arm or a wall, which also takes up less desktop space.

More adjustable - LCD displays are much more adjustable than CRT displays. With LCDs, you can adjust the tilt, height, swivel, and orientation from horizontal to vertical mode. As noted previously, you can also mount them on the wall or on an arm.

Less eye strain - Because LCD displays turn each pixel off individually, they do not produce a flicker like CRT displays do. In addition, LCD displays do a better job of displaying text compared with CRT displays

Computer screen resolution

Graphics resolution is measured in pixels. A pixel is a distinct point of light displayed on a

monitor. The quality of a computer screen is defined by the

number of horizontal and vertical pixels that can be displayed.

For example a widescreen monitor may be able to display 1280 x 1024 pixels with millions of colors.

As for image resolution in digital cameras, it is measured by the number of mega pixels that can captured in a photograph.