A+ 1001: Power Supply

Question 1

Auto-sensing power supply

Answer 1

Senses power input and auto adjusts

Question 2

Step Down Transformers

Answer 2

PSU are step down transformers that converts AC to DC

Question 3

ATX Power connector

Answer 3

20 to 24 pin connector

Yellow: 12volt:

Red: 5 volts

Orange 3.3 volts

Question 4

ATX12v

Answer 4

Extension Power connectors that provide extra power to mother board

Question 5

Molex

Question 6

Mini connector

Question 7

Connectors coming from the power supply

Answer 7

1. ATX
2. ATX12V
3. Molex (peripherals)
4. Mini connectors (peripherals)
5. SATA power connection (drives)
6. PCI-E connector (video cards)

Question 8

What makes modular connectors different

Answer 8

The cables are not soldered to them, which means you only have to attach the cables that are needed, it makes cable management easier.

The trade off is that the modular connections loses a bit of efficiency

Question 9

How calculate the required wattage of power supply

Answer 9

multiply the total amps of all components by the total volts of all components

Many modern gaming systems with a 6 or 8-core CPU and a midrange to high-end graphics card should get by with a 650W to 850W power supply, with 750W being a long-time sweet spot for gamers. More powerful hardware requires higher wattages, especially if you plan on overclocking

Question 10

What factors to consider when choosing a PSU

Answer 10

1. Required Wattage
2. Room Temperature

Building to about 50 to 60 percent of a PSU’s capacity is advisable to achieve maximum efficiency and yet leave room for future expansion.

Question 11

80 plus rating system

Answer 11

A standard that guarantees PSU efficiency at 80%

Question 12

What happens when a system overheats?

Answer 12

Reboots

Question 13

How to reduce fan noise?

Answer 13

use bigger fans that turn slower but move the same amount of air

Question 14

PWM connectors

Answer 14

4 pin connectors that are used by the CPU to modulate fan speed directly

Question 15

How to regulate temp of system?

Answer 15

set temperature warnings in the BIOS

Set temperature a little lower than the cpu max

Question 15

How to regulate temp of system?

Answer 15

set temperature warnings in the BIOS

Set temperature a little lower than the cpu max

Question 16

Which component within a computer is the most likely to die?

Answer 16

Power supply

Question 17

Slow death of PSU.

Answer 17

The primary capacitors that act as surge surpressors start to break down, which results in a slow death.

Symptoms:

• Unexpected shutdowns
• unplug it and replug it then it works for a while

Question 18

Testing PSU

Answer 18

voltage tester
- look for voltage drops

Fan Spin Test
- connect PGW (green wire), with any ground wire (Black wire) using a paperclip, and see if the fan spins

Motherboard Test

• plug into old motherboard
• Set Voltmeter to 20V DC
• Red Pin to yellow wire(12V)
• Black pin to black wire (ground)
• connect pins that attaches to on button, using a hairclip or jumper
• Read Voltage

If voltage drops to 11.5 then get a new power supply.

Question 19

Test core components before mounting to case

Answer 19

Startup computer to bios screen

1. Check that fans are spinning
2. Check for POST error codes
3. Check for onboard LEDs
4. Check BIOS to see if hardware is connected
5. Boot to windows from thumbdrive and perform a memory diagnostic

if the computer is dead then start over and reassemble the build.

if you get system lockup, clear the CMOS jumper

Question 20

Cause of dead PC

Answer 20

Incorrectly installed CPU’s or RAM (Reinstall)

Error is system setup (Clear CMOS jumper)

Power supply not connected (check connections)

Question 21

A power supply with optional cable plug-ins is known as a what?

Answer 21

A modular power supply simplifies cable management by enabling you to add and remove optional plug-in cables as needed to power components.

Question 22

What does the on/off switch on a power supply do?

Answer 22

It allows power to flow from the plug into the power supply.

Question 23

The four/six/eight pin connector (known as the P4 connector) on the ATX 12V power supply provides power to which computer component(s)?

Answer 23

The ATX 12V power connectors send power to the CPU

Question 24

Which is a primary characteristic to be considered when choosing a power supply?

Answer 24

Efficiency is a major consideration.

Question 25

Which is the quietest cooling solution

Answer 25

Liquid cooling is the quietest solution. Fan noise varies depending on size and speed, but small fans (which have to spin faster to move the same amount of air) tend to be louder than large ones. SpeedFan is a fan controller program, not a cooling solution.

Question 26

What is the primary result of overheating the CPU?

Answer 26

CPU overheating causes shutdowns and reboots.

Overheating does not increase or decrease performance.

Overheating does not cause fans to spin faster.

Question 27

The voltages output by a PSU can be checked with which tool?

Answer 27

Power supply test tool can test the voltages

Question 28

Catastrophic (fast) power failures typically include which symptom?

Answer 28

Catastrophic power supply failure may be accompanied by a burning odor. A catastrophically-failed power supply is dead; it cannot provide enough power for slow performance or rebooting. Power supply voltage decay over time is a symptom of a slowly failing power supply.

Question 29

Unexpected noise coming from inside a running computer likely comes from what?

Answer 29

Cables or loose items in a case that contact spinning fan blades causes unpleasant and unexpected noise. Failing RAM only generates beep codes during the POST process at boot up. Failing speakers and overheated CPUs don’t usually make noise

Question 30

If installed RAM does not show up in the CMOS setup program, what is the best course of action?

Answer 30

Reseat the Ram modules