A+ Guide to Managing and Maintaining Your PC Fifth Edition Chapter 4 Electricity and Power Supplies.

A+ Guide to Managing and Maintaining Your PCFifth Edition

Chapter 4

Electricity and Power Supplies

2 A+ Guide to Managing and Maintaining Your PC, Fifth Edition

You Will Learn… How electricity is measured How to protect your computer system against

damaging changes in electrical power About different form factors and computer

cases How to detect and correct power supply

problems About Energy Star specifications


Measures of Electricity


AC and DC

Alternating current (AC) Cycles back and forth Economical

Direct current (DC) Travels in only one direction, from hot to ground Required by most electronic devices

Computer power supply functions as both a transformer and rectifier


Computer Power Supply


Hot, Neutral, and Ground


Hot, Neutral, and Ground (continued)


Hot, Neutral, and Ground (continued)


Common Electrical Components


Protecting Your Computer System: General Precautions Make notes so you can backtrack

Remove packing materials from work area

Keep components away from hair and clothing

Keep screws and spacers in an orderly place

Don’t stack boards on top of each other


Protecting Your Computer System: General Precautions (continued) Don’t touch chips on motherboard or

expansion cards

Don’t touch chip with magnetized screwdriver

Don’t change DIP switch settings with a graphite pencil


Protecting Your Computer System: General Precautions (continued) Have classroom instructor check your work

before putting cover on and powering up

Turn off a computer before moving it

Keep disks away from magnetic fields, heat, and extreme cold


Protecting Yourself Against Electricity Turn off power and unplug computer

Always use a ground bracelet

Never touch inside of a computer while it is turned on

Never remove cover or put your hands inside monitor or power supply


Static Electricity (or ESD)

Can cause catastrophic failure or upset failure

Protection against ESD

Ground bracelet or static strap

Ground mats

Static shielding bags


Ground Bracelet


Ground Bracelet with a Ground Mat


Static Shielding Bags


EMI (Electromagnetic Interference) Caused by magnetic field produced as side

effect when electricity flows

Protection against EMI

Cover expansion slots

Do not place system close to or on same circuit as high-powered electrical equipment

Use line conditioners


Surge Protection and Battery Backup Surge suppressors

Power conditioners

Uninterruptible power supplies (UPSs)


Uninterruptible Power Supplies Benefits

Condition line for brownouts and spikes Provide backup power during a blackout Protect against very high potentially damaging

spikes Considerations

Cost UPS rating Degree of line conditioning Warranty and service policies


UPS


The Computer Case and Form Factors

Form factor describes size, shape, and general makeup of a hardware component

Use same form factor for motherboard, case, and power supply

Decision driven by motherboard


Case, Power Supply, and Motherboard Form Factors AT

ATX (most popular)

LPX

NLX

Backplane systems


AT and Baby AT Form FactorsAT Form Factor Baby AT Form Factor Used on older motherboards Difficult to install, service,

and upgrade Uses two power connectors:

P8 and P9 Problematic position of CPU

in relation to expansion slots No longer produced by most

manufacturers

Industry standard from 1993-1997

Small; fits into many types of cases

Problematic position of CPU unresolved

Drives/devices not close to connections on motherboard


AT Motherboard


Power Connectors on AT and ATX Boards


ATX Form Factor Open, nonproprietary spec (Intel 1995)

Easier to add and remove components

Greater support for I/O devices and processor technology

Lower costs

Improved positioning of components


ATX Form Factor (continued) Smaller

Uses one power connector: P1

Soft switch feature

Better air circulation

Other types: Mini-ATX, MicroATX, FlexATX


ATX Motherboard


NLX Form Factor


Other Form Factors

LPX and Mini-LPX Backplane SystemsRiser card similar to

NLX systemsUsed in low-cost systemsDifficult to upgradeCannot handle size and

operating temperature of processors

Proprietary issues

Not a true motherboard; board sits against back of proprietary case with slots for other cards

Active backplanesPassive backplanes


Types of Cases

Desktop cases

Tower cases

Minitower

Midsize tower

Full-size tower

Notebook cases


Desktop Case


Tower Case


Tower and Desktop Cases


Upgrading Your Power Supply

Sometimes necessary when you add new devices

Easiest way to fix a power supply you suspect is faulty is to replace it


Introduction to Troubleshooting

Isolate the problem

Problems that prevent PC from booting

Problems that occur after a successful boot

Learn as much as you can by asking questions of user(s)


PC Problem Solving


Troubleshooting the Power System: General Guidelines Any burnt parts or odors?

Everything connected and turned on? Loose cable connections? Computer plugged in?

All switches turned on? Wall outlet good?

If fan is not running, turn off computer: Connections to power supply secure? Cards securely seated?


Troubleshooting the Power System: General Guidelines (continued) Check for correct wire connections to

motherboard

Remove nonessential expansion cards one at a time

Vacuum entire unit


Troubleshooting an ATX Power Supply


Troubleshooting the Power System Power supply itself

Power supply fan

Power problems with the motherboard

Overheating


Preventing Overheating


Preventing Overheating (continued)


Energy Star Systems(The Green Star)

Satisfy energy-conserving standards of the US EPA

Generally have a standby program that switches device to sleep mode when not in use

Apply to computers, monitors, printers, copiers, and fax machines


Power Management Methods

Advanced Power Management (APM)

AT Attachment (ATA) for IDE drives

Display Power Management Signaling (DPMS) standards for monitors and video cards

Advanced Configuration and Power Interface (ACPI)


Power Management Features Green timer on the motherboard

Doze time

Standby time

Suspend time

Hard drive standby time


Power Management Setup Screen


Energy Star Monitors

Most adhere to DPMS specifications

Allow video card and monitor to go into sleep mode simultaneously


Changing Power Options


Summary

Measurements of electricity

Form in which electricity comes to you as house current

The power supply, backup power sources, and how to change a defective power supply

Form factors

How Energy Star saves energy

A+ Guide to Managing and Maintaining Your PC Fifth Edition Chapter 4 Electricity and Power Supplies.

Documents

ground slide

edition ground bracelet

ground continued slide

edition ac

ground mat slide

edition chapter

rectifier slide

edition static electricity