Chapter 4 Disassembly and Power
description
Transcript of Chapter 4 Disassembly and Power
![Page 1: Chapter 4 Disassembly and Power](https://reader033.fdocuments.in/reader033/viewer/2022061600/56813d45550346895da7035e/html5/thumbnails/1.jpg)
© 2011 Pearson Addison-Wesley. All rights reserved.
Addison Wesley is an imprint of
Chapter 4Disassembly and Power
Chapter 4Disassembly and Power
The Complete A+ Guideto PC Repair 5/e
![Page 2: Chapter 4 Disassembly and Power](https://reader033.fdocuments.in/reader033/viewer/2022061600/56813d45550346895da7035e/html5/thumbnails/2.jpg)
© 2011 Pearson Addison-Wesley. All rights reserved.
Chapter ObjectivesChapter Objectives
After completing this chapter you will:Describe how static electricity can damage a computerDescribe what type of equipment causes RFI and EMI and what to do when they occurList tools a technician needsDisassemble and reassemble a computerDefine and apply basic electronic termsPerform basic checks, such as voltage and continuityDescribe the purposes of a power supplyInstall a power supply and connect the motherboard and devices to itRecognize the different power supply output voltagesRecognize different power connectors
![Page 3: Chapter 4 Disassembly and Power](https://reader033.fdocuments.in/reader033/viewer/2022061600/56813d45550346895da7035e/html5/thumbnails/3.jpg)
© 2011 Pearson Addison-Wesley. All rights reserved.
Chapter Objectives (cont.)Chapter Objectives (cont.)
After completing this chapter you will:Apply appropriate power saving techniquesResearch and upgrade or replace a power supplySolve power problems
Define and describe the purpose of different power protection devices
Describe what to do if an electrical fire occurs
Detail what to do when a computer component fails and must be thrown away
Detail alternatives for outdated computer
Describe good written communication techniques
1-3
![Page 4: Chapter 4 Disassembly and Power](https://reader033.fdocuments.in/reader033/viewer/2022061600/56813d45550346895da7035e/html5/thumbnails/4.jpg)
© 2011 Pearson Addison-Wesley. All rights reserved.
Disassembly OverviewDisassembly Overview
• It is seldom necessary to completely disassemble a computer.− Sometimes disassembly is accomplished to perform
a preventive maintenance cleaning.
• Disassembly is also helpful in diagnosing problems of undetermined cause by removing components one by one or outside the case.
• Disassembly can also help with diagnosing grounding problems.− Grounding – Occurs when motherboard or adapter isn’t properly
installed and a trace (metal line on the motherboard or adapter) touches the computer frame and causes the adapter or other components to stop working.
![Page 5: Chapter 4 Disassembly and Power](https://reader033.fdocuments.in/reader033/viewer/2022061600/56813d45550346895da7035e/html5/thumbnails/5.jpg)
© 2011 Pearson Addison-Wesley. All rights reserved.
Electrostatic Discharge (ESD)Electrostatic Discharge (ESD)
• ESD (ElectroStatic Discharge) – Occurs when stored up static
electricity is discharged in an instantaneous surge of voltage. ESD
damage is nonrecoverable and the most susceptible components are the
CMOS and RAM chips.
• Anti-static Wrist Strap – A strap connecting the technician to the
computer and that equalizes the voltage potential between the two to
prevent ESD. It is connected to a grounding post or a metal component
such as the power supply. − Electronic symbol for ground:
Warning: A technician should NEVER wear an ESD wrist strap when
working inside a monitor because of high voltages!
![Page 6: Chapter 4 Disassembly and Power](https://reader033.fdocuments.in/reader033/viewer/2022061600/56813d45550346895da7035e/html5/thumbnails/6.jpg)
© 2011 Pearson Addison-Wesley. All rights reserved.
Anti-Static Wrist StrapAnti-Static Wrist Strap
Disassembly – Figure 4.1
![Page 7: Chapter 4 Disassembly and Power](https://reader033.fdocuments.in/reader033/viewer/2022061600/56813d45550346895da7035e/html5/thumbnails/7.jpg)
© 2011 Pearson Addison-Wesley. All rights reserved.
EMI (Electromagnetic Interference)EMI (Electromagnetic Interference)
• EMI (ElectroMagnetic Interference) – Also called EMR (ElectroMagnetic Radiation) is noise caused by electrical devices. − Can travel through electrical wires.
• RFI (Radio Frequency Interference) – Noises that occur in the radio frequency range.
• Always replace the slot covers for expansion slots that are not being used. − This will keep out dust and improve the airflow inside
the computer.
![Page 8: Chapter 4 Disassembly and Power](https://reader033.fdocuments.in/reader033/viewer/2022061600/56813d45550346895da7035e/html5/thumbnails/8.jpg)
© 2011 Pearson Addison-Wesley. All rights reserved.
DisassemblyDisassembly
• As with most tasks, the successful disassembly of a computer begins with preparation. − Do not remove the motherboard battery− Use proper grounding − Take notes− Have ample workspace− Do not stack adapters− Use anti-static bags if possible− Handle adapter/motherboard by edges− Handle hard drives carefully− Do not disassemble a CRT monitor or power supply
![Page 9: Chapter 4 Disassembly and Power](https://reader033.fdocuments.in/reader033/viewer/2022061600/56813d45550346895da7035e/html5/thumbnails/9.jpg)
© 2011 Pearson Addison-Wesley. All rights reserved.
ToolsTools
Important
Tools to
Have
Medium flat-tipped screwdriver
Small flat-tipped “tweaker” screwdriver
#1 Phillips screwdriver
#2 Phillips screwdriver
¼-inch nut driver
3/16-inch nut driver
Small diagonal cutters
Needlenose pliers
• Having the proper tools to disassemble the computer can make the task easier and prevent damage to computer components.
![Page 10: Chapter 4 Disassembly and Power](https://reader033.fdocuments.in/reader033/viewer/2022061600/56813d45550346895da7035e/html5/thumbnails/10.jpg)
© 2011 Pearson Addison-Wesley. All rights reserved.
ReassemblyReassembly
• Reassembly is easily accomplished if the technician is careful and diagrams properly during disassembly. Exercise care and reinstall all components to their original location.
• Three major reassembly components – Motherboards
• Have plastic connectors on the bottom called standoffs.• Standoffs – Plastic connectors on the bottom side of a
motherboard that attach it to the case and prevent it from being in contact with the metal of the computer case.
– Cables– Connectors
![Page 11: Chapter 4 Disassembly and Power](https://reader033.fdocuments.in/reader033/viewer/2022061600/56813d45550346895da7035e/html5/thumbnails/11.jpg)
© 2011 Pearson Addison-Wesley. All rights reserved.
Cables and ConnectorsCables and Connectors
• Keyed – A connector or cable that has an extra metal piece that allows correct connections.
Disassembly – Figure 4.4
![Page 12: Chapter 4 Disassembly and Power](https://reader033.fdocuments.in/reader033/viewer/2022061600/56813d45550346895da7035e/html5/thumbnails/12.jpg)
© 2011 Pearson Addison-Wesley. All rights reserved.
Cables and ConnectorsCables and Connectors
• Pin 1 – Pin 1 on a cable should be connected to Pin 1 on the connector. The colored stripe on the edge of the cable identifies Pin 1 on the cable.− Pin 1 on an adapter will be stenciled beside the connector.
Ribbon Cable’s Pin 1
Disassembly – Figure 4.2
![Page 13: Chapter 4 Disassembly and Power](https://reader033.fdocuments.in/reader033/viewer/2022061600/56813d45550346895da7035e/html5/thumbnails/13.jpg)
© 2011 Pearson Addison-Wesley. All rights reserved.
Cables and ConnectorsCables and Connectors
• Solder Joints – Solder connections on the back of motherboards and adapters. Pin 1 solder joints on the back of connectors are square.
Pin 1 on a Connector
Disassembly – Figure 4.5
![Page 14: Chapter 4 Disassembly and Power](https://reader033.fdocuments.in/reader033/viewer/2022061600/56813d45550346895da7035e/html5/thumbnails/14.jpg)
© 2011 Pearson Addison-Wesley. All rights reserved.
Hard DrivesHard Drives
• Hard drives must be handled carefully during disassembly because of the delicate nature of their very intricate construction.– The read/write heads are located only millimeters from
the platter storing all the data. A small jolt can cause them to make contact with the platter and cause permanent physical damage.
• Self-Parking Heads – Read/write heads which pull away automatically when the computer powers off. − This feature still would not prevent damaged caused by
an accident or mishandling.
![Page 15: Chapter 4 Disassembly and Power](https://reader033.fdocuments.in/reader033/viewer/2022061600/56813d45550346895da7035e/html5/thumbnails/15.jpg)
© 2011 Pearson Addison-Wesley. All rights reserved.
Preventive MaintenancePreventive Maintenance
• Preventive Maintenance – Certain procedures performed to prolong the life of the computer, such as cleaning the computer, drive heads, keyboard keys, printers, and monitor screen.
• MSDS (Material Safety Data Sheets) – Sheets that contain information about a product, its toxicity, storage, and disposal.
![Page 16: Chapter 4 Disassembly and Power](https://reader033.fdocuments.in/reader033/viewer/2022061600/56813d45550346895da7035e/html5/thumbnails/16.jpg)
© 2011 Pearson Addison-Wesley. All rights reserved.
Tech TipsTech Tips
• LCD monitor cleaning– Use wipes specifically made for LCDs
– Soft lint-free cloth dampened with water or a mixture of isopropyl alcohol and water
– Don’t close laptop lid until screen is dry
• Aerosol can disposal– Some states have special requirements
• During preventive maintenance calls…– Check for system, driver, and anti-virus updates
16
![Page 17: Chapter 4 Disassembly and Power](https://reader033.fdocuments.in/reader033/viewer/2022061600/56813d45550346895da7035e/html5/thumbnails/17.jpg)
© 2011 Pearson Addison-Wesley. All rights reserved.
Basic Electronics OverviewBasic Electronics Overview
• A technician should know a few basic electronic terms and concepts when working with computers and testing components.
• Electricity (or power) - Electrons flowing through a conductor, just like water flows through a pipe.
• The two types of electricity– AC (Alternating Current) – Electricity where electrons flow in both
directions and is provided by a wall outlet. Radios, toasters, and televisions are some devices that use AC power.
– DC (Direct Current) – Electricity where the electrons flow in only one direction. Low voltage DC power is used by computer components, or anything with batteries. The computer’s power supply converts AC from the wall to DC for use by internal computer components.
![Page 18: Chapter 4 Disassembly and Power](https://reader033.fdocuments.in/reader033/viewer/2022061600/56813d45550346895da7035e/html5/thumbnails/18.jpg)
© 2011 Pearson Addison-Wesley. All rights reserved.
Electronic TermsElectronic Terms
• Voltage – A measure of the pressure pushing electrons through a circuit. – Measured in volts– Power supply output is measured in volts (DC) and are typically
+3.3 volts, +5 volts, - 5 volts, +12 volts, and –12 volts. – The + or – refers to polarity which is simply the condition of
being either positive or negative with respect to some voltage point, usually 0 volts, or ground.
• Capacitor – A component that holds a charge even after the computer is turned off. – CRT monitors have capacitors that can stay charged with high
voltage for hours after being turned off. – Measured in farads
![Page 19: Chapter 4 Disassembly and Power](https://reader033.fdocuments.in/reader033/viewer/2022061600/56813d45550346895da7035e/html5/thumbnails/19.jpg)
© 2011 Pearson Addison-Wesley. All rights reserved.
DC Voltage ReadingDC Voltage Reading
19
• Ensure the polarity (black to ground) is maintained when taking DC voltage readings.
![Page 20: Chapter 4 Disassembly and Power](https://reader033.fdocuments.in/reader033/viewer/2022061600/56813d45550346895da7035e/html5/thumbnails/20.jpg)
© 2011 Pearson Addison-Wesley. All rights reserved.
Electronic TermsElectronic Terms
• Current –The number of electrons going through a circuit every second. • Measured in amps (amperes) • Every device needs some current to operate and a power supply
may be rated at the total amount of current it can supply at a certain voltage level, such as 20 amps at the 5-volt level, or 8 amps at the 12-volt level.
• Power – How much electrical work is being done. • Measured in watts• Calculated by multiplying volts times amps. • Power supplies are described as providing a maximum number
of watts.
![Page 21: Chapter 4 Disassembly and Power](https://reader033.fdocuments.in/reader033/viewer/2022061600/56813d45550346895da7035e/html5/thumbnails/21.jpg)
© 2011 Pearson Addison-Wesley. All rights reserved.
Electronic TermsElectronic Terms
• Resistance –The amount of opposition to current in an electronic circuit. − Measured in ohms− A good cable or fuse will have very low resistance (close to zero).− A broken wire or bad fuse will have very high resistance (millions of
ohms, sometimes displayed as infinite).
• Continuity – A connection from one end of a wire to another.
− Good continuity means little or no resistance. − Bad continuity means high or infinite resistance, such as with a broken
wire in a cable or a bad fuse. − Continuity checks can also be used to determine which connector pins
on one end of a cable are attached to what pins on the other connector end.
![Page 22: Chapter 4 Disassembly and Power](https://reader033.fdocuments.in/reader033/viewer/2022061600/56813d45550346895da7035e/html5/thumbnails/22.jpg)
© 2011 Pearson Addison-Wesley. All rights reserved.
Electronic TermsElectronic Terms
• The sample meter readings in figure 4.7 demonstrate a good connection - good continuity or zero resistance, also known as a short, as well as a broken wire – bad continuity or infinite resistance, also known as an open.
Power – Figure 4.7
![Page 23: Chapter 4 Disassembly and Power](https://reader033.fdocuments.in/reader033/viewer/2022061600/56813d45550346895da7035e/html5/thumbnails/23.jpg)
© 2011 Pearson Addison-Wesley. All rights reserved.
Power Supply OverviewPower Supply Overview
• The power supply is an essential component because none of the other components can function without it. – Converts AC to DC– Distributes lower voltage to computer components– Provides cooling with its fan.– It can be the source of strange and hard to diagnose
problems and easily causes damage to other internal components.
– Two basic types of power supplies • Switching (requires a load or something attached to it using current),
which is the type used by a computer
• Linear (provides constant voltage)
![Page 24: Chapter 4 Disassembly and Power](https://reader033.fdocuments.in/reader033/viewer/2022061600/56813d45550346895da7035e/html5/thumbnails/24.jpg)
© 2011 Pearson Addison-Wesley. All rights reserved.
Power Supply Form FactorsPower Supply Form Factors
• Power supplies have form factors (shapes and sizes) like motherboards do. Form factors today are the ATX, ATX12V v1.x, and ATX12V v2.x.
• Specific models− LFX12V – low profile− SFX12V – small form factor− EPS12V – used with server motherboards and has an extra
8-pin connector− CFX12V – compact form factor− TFX12V – thin form factor− WFX12V – used with high-end workstations and some
servers
![Page 25: Chapter 4 Disassembly and Power](https://reader033.fdocuments.in/reader033/viewer/2022061600/56813d45550346895da7035e/html5/thumbnails/25.jpg)
© 2011 Pearson Addison-Wesley. All rights reserved.
Power Supply Form FactorsPower Supply Form Factors
![Page 26: Chapter 4 Disassembly and Power](https://reader033.fdocuments.in/reader033/viewer/2022061600/56813d45550346895da7035e/html5/thumbnails/26.jpg)
© 2011 Pearson Addison-Wesley. All rights reserved.
ATX Power SupplyATX Power Supply
Power – Figure 4.8
![Page 27: Chapter 4 Disassembly and Power](https://reader033.fdocuments.in/reader033/viewer/2022061600/56813d45550346895da7035e/html5/thumbnails/27.jpg)
© 2011 Pearson Addison-Wesley. All rights reserved.
ATX Power Supply ConnectorsATX Power Supply Connectors
27
![Page 28: Chapter 4 Disassembly and Power](https://reader033.fdocuments.in/reader033/viewer/2022061600/56813d45550346895da7035e/html5/thumbnails/28.jpg)
© 2011 Pearson Addison-Wesley. All rights reserved.
Power Supply Tech TipsPower Supply Tech Tips
• Replace a bad power supply with one of equal or greater wattage.– A rule of thumb is that if two power supplies are
equal in wattage, the heavier one is better because it uses a bigger transformer, bigger heat sinks, and more quality components.
• Not all 24-pin motherboard connectors can accept the 20-pin power supply connector (older ATX power supply). – Obtain a 24- to 20-pin adapter
28
![Page 29: Chapter 4 Disassembly and Power](https://reader033.fdocuments.in/reader033/viewer/2022061600/56813d45550346895da7035e/html5/thumbnails/29.jpg)
© 2011 Pearson Addison-Wesley. All rights reserved.
Power Converters and Y ConnectorsPower Converters and Y Connectors
• Good to have in the tool kit
29
Y ConnectorBerg-to-Molex Converter
Molex-to-SATA Converter
![Page 30: Chapter 4 Disassembly and Power](https://reader033.fdocuments.in/reader033/viewer/2022061600/56813d45550346895da7035e/html5/thumbnails/30.jpg)
© 2011 Pearson Addison-Wesley. All rights reserved.
Purposes of a Power SupplyPurposes of a Power Supply
• Purposes of the power supply– Convert AC wall outlet voltage to DC voltage.– Create and distribute lower DC voltages to
internal components throughout the computer.– Provide cooling to the computer with its fan.
![Page 31: Chapter 4 Disassembly and Power](https://reader033.fdocuments.in/reader033/viewer/2022061600/56813d45550346895da7035e/html5/thumbnails/31.jpg)
© 2011 Pearson Addison-Wesley. All rights reserved.
WarningsWarnings
WARNING!
The power supply contains potentially lethal voltages and current!
• To prevent injury, possible death, or damage to the computer− ALWAYS exercise extreme caution when working inside the computer if it
is plugged into the wall outlet and/or the power supply is operating. − UNPLUG the computer from AC power (power cable from wall outlet to the
power supply) when working with wires (such as connecting the front panel power switch) or connecting/disconnecting internal power cables.
− ALWAYS follow ALL the manufacturer’s safety warnings and instructions for connecting the power supply or working inside the computer.
![Page 32: Chapter 4 Disassembly and Power](https://reader033.fdocuments.in/reader033/viewer/2022061600/56813d45550346895da7035e/html5/thumbnails/32.jpg)
Tech TipsTech Tips
Powering on a power supply without
anything attached could damage the
power supply.
Powering on a power supply without
anything attached could damage the
power supply.
PowerPower
An ATX power supply usually requires only
a motherboard connection as a minimum load.
An ATX power supply usually requires only
a motherboard connection as a minimum load.
![Page 33: Chapter 4 Disassembly and Power](https://reader033.fdocuments.in/reader033/viewer/2022061600/56813d45550346895da7035e/html5/thumbnails/33.jpg)
© 2011 Pearson Addison-Wesley. All rights reserved.
Front Panel Power ConnectorsFront Panel Power Connectors
Power –Figure 4.13
![Page 34: Chapter 4 Disassembly and Power](https://reader033.fdocuments.in/reader033/viewer/2022061600/56813d45550346895da7035e/html5/thumbnails/34.jpg)
© 2011 Pearson Addison-Wesley. All rights reserved.
Power Supply ATX ConnectorPower Supply ATX Connector
Power – Figure 4.14
![Page 35: Chapter 4 Disassembly and Power](https://reader033.fdocuments.in/reader033/viewer/2022061600/56813d45550346895da7035e/html5/thumbnails/35.jpg)
© 2011 Pearson Addison-Wesley. All rights reserved.
Power Supply VoltagesPower Supply Voltages
• The wires from the power supply carry the following levels of DC voltage:– (+) 5 volts: motherboard, most adapters, CD/DVD and
hard drive, some newer drive motors, some chips– (-) 5 volts: seldom used– (+) 12 volts: CD/DVD and hard drives (for internal
motors)– (-) 12 volts: seldom used– (+) 3.3 volts: some chips on motherboards, including
CPUs; also memory, PCI/PCIe adapters, and some laptop fans
![Page 36: Chapter 4 Disassembly and Power](https://reader033.fdocuments.in/reader033/viewer/2022061600/56813d45550346895da7035e/html5/thumbnails/36.jpg)
© 2011 Pearson Addison-Wesley. All rights reserved.
Power Supply VoltagesPower Supply Voltages
• Occasionally voltages must be checked on a system. There are four basic power supply checks that can be accomplished:− Wall outlet AC voltage− DC voltages going to the motherboard− DC voltages going to a device − Ground with an outlet tester
• A power supply tester be used to check DC power levels on the different connectors.
• Exercise extreme caution when checking AC voltages because voltages harmful to the technician are present!
![Page 37: Chapter 4 Disassembly and Power](https://reader033.fdocuments.in/reader033/viewer/2022061600/56813d45550346895da7035e/html5/thumbnails/37.jpg)
© 2011 Pearson Addison-Wesley. All rights reserved.
Laptop Travel and StorageLaptop Travel and Storage
• When traveling with a laptop:– Remove all cards that insert into slots.– Remove of media disks.– Ensure that all drive doors and devices are securely
latched.– Check that the laptop is powered off or in hibernate
mode.– Carry laptop in a padded case. Never lay laptop
upside down on conveyor belt. – Never pick a laptop up by the display when the laptop
is opened.
1-37
![Page 38: Chapter 4 Disassembly and Power](https://reader033.fdocuments.in/reader033/viewer/2022061600/56813d45550346895da7035e/html5/thumbnails/38.jpg)
© 2011 Pearson Addison-Wesley. All rights reserved.
Laptop Power with TravelLaptop Power with Travel
Reduce screen
brightness
Turn off wireless if possible
Avoid using DVD/CD drive.
Configure for Hibernate rather than Standby
Keep battery contacts clean
Seldom save documents—Turn off autosave
Fragment the hard drivebefore leaving
Avoid using multiple applications
Avoid using USB
devices
Avoid temperature extremes
![Page 39: Chapter 4 Disassembly and Power](https://reader033.fdocuments.in/reader033/viewer/2022061600/56813d45550346895da7035e/html5/thumbnails/39.jpg)
© 2011 Pearson Addison-Wesley. All rights reserved.
Laptop OverheatingLaptop Overheating
39
BIOS settings
Keep them unblocked and clean. Do not place the computer on your lap to work.
Locate air vents
Check temperature settings for when the fans turn on.
Check manufacturer web siteCheck for any fan/temperature monitoring gauges are
available through BIOS or applications
Pads, trays, and mats can be purchased with fans that are AC or USB-powered
Elevate the laptop
![Page 40: Chapter 4 Disassembly and Power](https://reader033.fdocuments.in/reader033/viewer/2022061600/56813d45550346895da7035e/html5/thumbnails/40.jpg)
© 2011 Pearson Addison-Wesley. All rights reserved.
Laptop PowerLaptop Power
• Laptops either use a battery (DC power) or an AC connection.
• On most models, the battery recharges when the laptop has AC power attached.
• Some power supplies and laptops have input voltage selectors.– Others have the ability to accept input from
100 to 240 volts for use in various countries.
40
![Page 41: Chapter 4 Disassembly and Power](https://reader033.fdocuments.in/reader033/viewer/2022061600/56813d45550346895da7035e/html5/thumbnails/41.jpg)
© 2011 Pearson Addison-Wesley. All rights reserved.
Laptop TipsLaptop Tips
• Most laptops use Li-ion batteries.– These batteries last longer if they are kept
cool. • 40% charged and place in refrigerator
• Don’t power on after a temperature change– Allow to return to room temperature– Avoid direct sunlight
41
![Page 42: Chapter 4 Disassembly and Power](https://reader033.fdocuments.in/reader033/viewer/2022061600/56813d45550346895da7035e/html5/thumbnails/42.jpg)
© 2011 Pearson Addison-Wesley. All rights reserved.
ACPI (Advanced Configuration and Power Interface)ACPI (Advanced Configuration and Power Interface)
• Allows the operating system, BIOS, and motherboard to have control over various devices’ power and modes of operation− CPU− Monitor− CD/DVD drive− Network adapter− Printer
• Two common BIOS and adapter features that take advantage of ACPI− Wake on LAN allows a network administrator to control power to a
workstation and come out of sleep mode for operating system, application, and anti-virus updates.
− Wake on Ring allows a computer to come out of sleep mode to receive phone calls, faxes, and e-mails.
![Page 43: Chapter 4 Disassembly and Power](https://reader033.fdocuments.in/reader033/viewer/2022061600/56813d45550346895da7035e/html5/thumbnails/43.jpg)
ACPI Operating StatesACPI Operating States
43
![Page 44: Chapter 4 Disassembly and Power](https://reader033.fdocuments.in/reader033/viewer/2022061600/56813d45550346895da7035e/html5/thumbnails/44.jpg)
Common BIOS Power SettingsCommon BIOS Power Settings
44
![Page 45: Chapter 4 Disassembly and Power](https://reader033.fdocuments.in/reader033/viewer/2022061600/56813d45550346895da7035e/html5/thumbnails/45.jpg)
© 2011 Pearson Addison-Wesley. All rights reserved.
ACPI and Coming Out of Sleep ModeACPI and Coming Out of Sleep Mode
• Sometimes a computer will not come out of sleep mode and the power or reset button has to be pressed.– A screen saver conflicts with ACPI– Not all adapters or devices are ACPI-compliant– An adapter or device has an outdated driver
• Keep the screen saver timeout value shorter than the power saver timeout value with energy efficient monitors.
![Page 46: Chapter 4 Disassembly and Power](https://reader033.fdocuments.in/reader033/viewer/2022061600/56813d45550346895da7035e/html5/thumbnails/46.jpg)
© 2011 Pearson Addison-Wesley. All rights reserved.
ACPI and Not Going into Sleep ModeACPI and Not Going into Sleep Mode
• Sometimes a computer will not go into sleep mode.– Determine if ACPI is enabled in the BIOS– Try disabling the antivirus application– Disable the screen saver to see if it is the problem– Determine if all drivers are ACP-compliant – Determine if power management is enabled through
the operating system– Disconnect USB devices
![Page 47: Chapter 4 Disassembly and Power](https://reader033.fdocuments.in/reader033/viewer/2022061600/56813d45550346895da7035e/html5/thumbnails/47.jpg)
© 2011 Pearson Addison-Wesley. All rights reserved.
Replacing or Upgrading a Power SupplyReplacing or Upgrading a Power Supply
• Its important to make sure that the power supply has enough power to run all the devices in the computer.
• If you’re adding or upgrading devices, make sure you won’t be exceeding the wattage rating for the power supply with the new configuration.
• If you upgrade or replace the power supply, make sure its power rating is high enough to meet the needs of the computer configuration and the power supply is the right size and form factor to fit the computer case.
![Page 48: Chapter 4 Disassembly and Power](https://reader033.fdocuments.in/reader033/viewer/2022061600/56813d45550346895da7035e/html5/thumbnails/48.jpg)
© 2011 Pearson Addison-Wesley. All rights reserved.
Replacing or Upgrading a Power SupplyReplacing or Upgrading a Power Supply
• Dual rail power supply – has two +12V output lines, one used for the CPU.
• Triple rail power supply – has three +12V output lines for devices.
• Multi-core processors and video cards use 12V power in addition to devices that have motors such as hard drives and CD/DVD drives.• Ensure enough amperage is provided for all installed devices
that use 12V power.
• An auto-switching power supply monitors incoming voltage and automatically switches itself accordingly. • Commonly found in laptops
![Page 49: Chapter 4 Disassembly and Power](https://reader033.fdocuments.in/reader033/viewer/2022061600/56813d45550346895da7035e/html5/thumbnails/49.jpg)
© 2011 Pearson Addison-Wesley. All rights reserved.
Replacing or Upgrading a Power SupplyReplacing or Upgrading a Power Supply
![Page 50: Chapter 4 Disassembly and Power](https://reader033.fdocuments.in/reader033/viewer/2022061600/56813d45550346895da7035e/html5/thumbnails/50.jpg)
© 2011 Pearson Addison-Wesley. All rights reserved.
Sample Computer +12V UsageSample Computer +12V Usage
![Page 51: Chapter 4 Disassembly and Power](https://reader033.fdocuments.in/reader033/viewer/2022061600/56813d45550346895da7035e/html5/thumbnails/51.jpg)
© 2011 Pearson Addison-Wesley. All rights reserved.
Power Supply ProblemsPower Supply Problems
• You should never take the power supply apart unless you have a
background in electronics. Replace the entire power supply when it is faulty;
power supplies are inexpensive.
• Power supply problems are usually easy to check. You should:
– Check to see that the power supply is plugged into the wall outlet and
snugly into the power supply. Replace it to verify functionality.
– If the power supply has never worked before, check the 115/230 switch
to be sure its in the 115 position.
– Ensure the power supply fan is turning. If not, check the wall outlet for
proper AC voltages with an AC circuit tester.
– If a surge strip is used, make sure its powered on, then try another
outlet in the strip, or another strip to verify functionality.
![Page 52: Chapter 4 Disassembly and Power](https://reader033.fdocuments.in/reader033/viewer/2022061600/56813d45550346895da7035e/html5/thumbnails/52.jpg)
Symptoms of Power Supply ProblemsSymptoms of Power Supply Problems
• The computer’s power light is off.• The power supply fan does not
turn with computer powered on.• The computer sounds a
continuous beep.• When the computer powers on, it
does not beep at all.• When the computer powers on, it
sounds repeating short beeps.
• During POST, a 02X or parity POST error code appears (where X is any number).
• The computer reboots without warning.
• The power supply fan is noisy.• The power supply is too hot to
touch.• The monitor power light is on, but
nothing appears. No PC power light is on.
![Page 53: Chapter 4 Disassembly and Power](https://reader033.fdocuments.in/reader033/viewer/2022061600/56813d45550346895da7035e/html5/thumbnails/53.jpg)
© 2011 Pearson Addison-Wesley. All rights reserved.
Adverse Power ConditionsAdverse Power Conditions
• Do not create a trip hazard with a surge strip
![Page 54: Chapter 4 Disassembly and Power](https://reader033.fdocuments.in/reader033/viewer/2022061600/56813d45550346895da7035e/html5/thumbnails/54.jpg)
© 2011 Pearson Addison-Wesley. All rights reserved.
Adverse Power ProtectionAdverse Power Protection
• Although power supplies have built-in protection against adverse power conditions, the best protection for a computer during a power outage or thunderstorm is to unplug it.
• Three devices are commonly used to protect the power supply from adverse conditions. They are:• A surge protector• A line conditioner• An Uninterruptible Power Supply (UPS)
![Page 55: Chapter 4 Disassembly and Power](https://reader033.fdocuments.in/reader033/viewer/2022061600/56813d45550346895da7035e/html5/thumbnails/55.jpg)
© 2011 Pearson Addison-Wesley. All rights reserved.
Surge ProtectorsSurge Protectors
• Surge protector – Is commonly a six-outlet strip with built-in protection against overvoltage.
• MOV (Metal Oxide Varistor) – An electronic component in most surge protectors that protects the computer or device that plugs into one of the outlets on the surge strip.
Power –Figure 4.17
![Page 56: Chapter 4 Disassembly and Power](https://reader033.fdocuments.in/reader033/viewer/2022061600/56813d45550346895da7035e/html5/thumbnails/56.jpg)
© 2011 Pearson Addison-Wesley. All rights reserved.
Surge Protector FeaturesSurge Protector Features
![Page 57: Chapter 4 Disassembly and Power](https://reader033.fdocuments.in/reader033/viewer/2022061600/56813d45550346895da7035e/html5/thumbnails/57.jpg)
© 2011 Pearson Addison-Wesley. All rights reserved.
Line ConditionersLine Conditioners
• Line Conditioners – protect the computer from overvoltages, undervoltages, and adverse noise conditions over electrical lines.– The line conditioner monitors AC electricity
and adjusts the voltage being sent to the computer.
![Page 58: Chapter 4 Disassembly and Power](https://reader033.fdocuments.in/reader033/viewer/2022061600/56813d45550346895da7035e/html5/thumbnails/58.jpg)
© 2011 Pearson Addison-Wesley. All rights reserved.
Uninterruptable Power Supply (UPS)Uninterruptable Power Supply (UPS)
• UPS (Uninterruptable Power Supply) – Provides power to a computer or device for a limited amount of time when there is a power outage. If the power from the wall outlet goes out, the battery continues to provide power for at least long enough to shut down the computer properly.
• Sine Wave – Pattern for AC voltage in its correct form and what you want the UPS you choose to have for its output.
• Square Wave – The AC voltage pattern described by cheaper, and thus less effective, UPS.
• Troubleshooting guidelines are listed on pages 131-132.
![Page 59: Chapter 4 Disassembly and Power](https://reader033.fdocuments.in/reader033/viewer/2022061600/56813d45550346895da7035e/html5/thumbnails/59.jpg)
© 2011 Pearson Addison-Wesley. All rights reserved.
Uninterruptable Power Supply (UPS)Uninterruptable Power Supply (UPS)
• Three things to look for when purchasing a UPS are to be sure that:– There is sufficient battery time
to protect all devices.– The amount of current the
UPS produces is sufficient to protect all devices.
– The output waveform is a sine wave.
![Page 60: Chapter 4 Disassembly and Power](https://reader033.fdocuments.in/reader033/viewer/2022061600/56813d45550346895da7035e/html5/thumbnails/60.jpg)
© 2011 Pearson Addison-Wesley. All rights reserved.
Standby Power Supply (SPS)Standby Power Supply (SPS)
• SPS (Standby Power Supply) – Provides power to a computer only when it loses AC power.– Does not provide protection against noise or
over/under voltages.– The SPS must detect a power-out condition first and
then switch over to the battery. Because of this, switching time is very important. Any time under five milliseconds is acceptable.
![Page 61: Chapter 4 Disassembly and Power](https://reader033.fdocuments.in/reader033/viewer/2022061600/56813d45550346895da7035e/html5/thumbnails/61.jpg)
© 2011 Pearson Addison-Wesley. All rights reserved.
Phone Line IsolatorPhone Line Isolator
• Phone line isolator – Also called a modem isolator, provides protection against phone line surges.– Goes in between a modem and the wall jack
to protect the computer against power surges on the phone line.
– Sometimes contained in a surge strip
![Page 62: Chapter 4 Disassembly and Power](https://reader033.fdocuments.in/reader033/viewer/2022061600/56813d45550346895da7035e/html5/thumbnails/62.jpg)
© 2011 Pearson Addison-Wesley. All rights reserved.
Electrical FiresElectrical Fires
• Electrical fires in computers are uncommon, but can still occur. If possible, unplug the computer if there is an electrical fire, but don’t risk injury to do so.– Type C Fire Extinguisher – A type of extinguisher
used only on electrical fires.– Type A-B-C Fire Extinguisher – A type of
extinguisher used on either Type A (wood, paper, cloth), Type B (flammable liquids or gases), or Type C fires.
![Page 63: Chapter 4 Disassembly and Power](https://reader033.fdocuments.in/reader033/viewer/2022061600/56813d45550346895da7035e/html5/thumbnails/63.jpg)
© 2011 Pearson Addison-Wesley. All rights reserved.
Computer Disposal/RecyclingComputer Disposal/Recycling
• Computers and electronic devices can contain materials which pose a threat to the environment such as: lead, cadmium, mercury, nickel, and zinc.
• Every state has regulations for disposing of electronic equipment.
1-63
![Page 64: Chapter 4 Disassembly and Power](https://reader033.fdocuments.in/reader033/viewer/2022061600/56813d45550346895da7035e/html5/thumbnails/64.jpg)
© 2011 Pearson Addison-Wesley. All rights reserved.
Alternatives to DisplosalAlternatives to Displosal
• Donate to schools and charities– If the operating system is not put on another system, leave
on the donated computer and provide proof of purchase.– Erase data stored on the donated computer
• Recycle outdated electronics– Many companies accept old parts and can reuse them
• Buy electronics designed with saving resources in mind and that are energy efficient.
• Check with the computer/component manufacturer to see if they have a recycling program.
64
![Page 65: Chapter 4 Disassembly and Power](https://reader033.fdocuments.in/reader033/viewer/2022061600/56813d45550346895da7035e/html5/thumbnails/65.jpg)
© 2011 Pearson Addison-Wesley. All rights reserved.
Written Communication SkillsWritten Communication Skills
• Technicians use written skills when documenting problems and writing emails.
• Documentation can include a basic description of what was done, and time spent on the job. • It should be written in a manner as to be helpful to
other technicians.
• Suggested guidelines for effective emails include using a spelling and grammar checker, and using proper capitalization, never only uppercase or lowercase letters.
1-65
![Page 66: Chapter 4 Disassembly and Power](https://reader033.fdocuments.in/reader033/viewer/2022061600/56813d45550346895da7035e/html5/thumbnails/66.jpg)
© 2011 Pearson Addison-Wesley. All rights reserved.
Effective EmailEffective Email
• Don’t use email when a meeting or phone call is more appropriate
• Include a subject in the email subject line• Do not write an email when angry• Send email only to the appropriate people• Stick to the point of the email; do not be wordy• Use a spell/grammar checker• Use proper grammar, capitalization, punctuation, and
spelling. • Do use all uppercase or lowercase letters.• Write each email as if it were being posted to a billboard.
66
![Page 67: Chapter 4 Disassembly and Power](https://reader033.fdocuments.in/reader033/viewer/2022061600/56813d45550346895da7035e/html5/thumbnails/67.jpg)
© 2011 Pearson Addison-Wesley. All rights reserved.
Addison Wesley is an imprint of
Questions???Questions???