How to Change a Power Pack on a Desktop Computer

Check the power cord before replacing the power supply.

When you push the power button on your computer, you expect to see the familiar welcome screen and logon options. But if the power supply goes out on your computer, all you will see when you push the power button is a blank screen. If you see no response when you power your computer on, the most likely culprit is a bad power supply. If you do encounter a bad power pack, you can buy a new one and replace it yourself.

Things You'll Need

• Screwdriver

Instructions

1. Shut down the computer and remove everything that is connected to it, including the keyboard, mouse and monitor and any printers, scanners or other peripherals. Remove the power cord from the computer as well.

2. Turn the computer around so the back of the case is facing you. Remove the retaining screws that hold the case to the computer chassis.

3. Pull the computer case off the chassis and locate the power supply. The power supply is typically located at the back of the computer case, just where the power cord plugs into the unit.

4. Trace each wire on the power supply to the component it powers. Remove each wire and flag it with a sticky note indicating the component into which it was plugged.

5. Remove the screws that secure the power supply to the computer chassis. Carefully lift the power supply out of the computer, taking note of how the power supply slides into the grooves in the chassis.

6. Slide the new power supply into the grooves that held the old pack. Push on the power supply until it snaps into place, then secure it with the screws.

7. Reattach each of the power cables to the new power supply. Replace the computer case, reconnect the peripherals and power on the computer.

Tips & Warnings

• Use a grounding strap to protect the computer's internal components.