Friend's computer won't boot, PSU dead?

[Catiaudo]

My friend has a p4 desktop that doesn't boot up anymore (it really doesn't do anything).... I go to check it out and plug the PSU cable into the wall and a really high pitched, constant noise comes from the computer. The yellow LED on the front of the case comes on and a green light by the RAM lights on the motherboard. The power and reset buttons do nothing. I'm assuming that it's a bad power supply but I don't have an extra one lying around to test. Any other ideas?

 

[Tigerbiten]

What the rest of the system/ bios.

The only Continuous beep comes from a IBM bios and is a power supply, system board, or keyboard problem.

The only thing to try is strip it down to the minimum needed to post and see if that makes any difference.

Luck........

 

[Catiaudo]

It's not a beep, its just a really high pitched squealing

 

[Tigerbiten]

Have you opened the case and tried to locate where the high pitched squealing is comeing from.

If from psu then probably a dead psu.

If from mobo then it could posibly be the overheat alarm.
Check on the seating of the heatsink, dust build up, fan.

Same with vidio card.

Luck..........