Repair computer

directly from a wall outlet, but instead needs a power supply to convert normal electricity into a lower wattage. If the power supply on your PC stops working, the computer either will not power on or will shut itself off at random times. Although your first instinct may be to take the PC to a technician, you can instead troubleshoot and repair the power supply on your own at home.
Difficulty: Moderate
Instructions
Things You'll Need
Screwdriver
Canned air
Replacement power supply fan
Replacement power supply
1

Unplug your PC's power cable and each of the other cords connected to the back of the case. Set the computer case on its side.
2

Remove the two screws at the back end of the case if the PC uses case screws. Grab the metal latch at the top of the case if there are no case screws present. Lift the latch up to unlock the side panel from the computer case.
3

Push down on the panel, and slide it off of the case. Remove the screws holding the power supply into place at the upper-left corner of the motherboard. Disconnect the cables running from the power supply to the motherboard.
4

Check to see if the power supply has a burning smell coming from it. Discard the power supply immediately if there is a burning scent; it will need to be replaced entirely.
5

See if the power supply fan is clogged with dust. Spray the fan with canned air to remove the debris. Reattach the power supply to the motherboard. Reassemble the computer and see if the problem persists.
6

Take the power supply out of the computer again if the problem continues. Check the model number on the side of the power supply. Check the manufacturer's Web site to see if you can acquire a replacement fan.
7

Remove the screws at the top of the power supply, and pull off the top half of the metal casing. Remove the screws holding the fan to the power supply case. Pull out the fan, and set in the replacement unit.
8

Reassemble the power supply and put the computer back together. Check to see if the problem continues. Acquire a new power supply if the problem continues.
9

Take the old power supply out of the computer again, and replace it with the new one. Attach the screws to hold the power supply to the case. Connect the power supply's cables to the motherboard.
10

Put the side panel back on the PC, then reattach the power cable. Power the computer on to make sure the power supply was installed correctly.