Unable to Solve System Issue

[Skrying]

Have a computer issue I'm trying to talk a friend through on the phone to fix it. It's been on going for about two weeks now and for the life of me I can't pin down what's the hardware failure. Here's the story/symptoms:

Friend wakes up and turns on computer but gets no display on monitor, no lights on keyboard or mouse. Have friend shut down the computer for 10 seconds, turn it on and it works.

Next morning friend calls again saying it's doing the same thing but shutting it down won't do anything this time. Have friend switch the PSU off in back of computer and unplug it, turn it on and it works.

Friend calls the next morning, same issue, nothing works. I try everything I can think of including clearing the CMOS by both jumper and battery. Nothing works.

So, we've replaced 1.) PSU, still same issue. 2.) New motherboard, still same issue. 3.) New video card, still same issue HOWEVER keeping the video card out of the system gets lights on the keyboard and mouse, though the mouse never goes away from its on state (optical, meaning light never dims).

The motherboard also only gives a beep code when the video card is out. Gives 5 short beeps, AMI bios which lists as CPU failure. I'm not sure if a CPU failure would cause these symptoms though.

Any ideas as to what the issue is would be greatly appreciated.

 

[cybereality]

Hard to say, I would think a power issue, but you said he got a new PSU. Make sure the PC is not plugged in to the wall. It should be on a capable surge-suppressor or even a UPS. However if there were any power issues (and the PC was plugged directly into the wall) then its possible some hardware got damaged. Although its hard to say, it really could be almost anything without knowing more.

 

[Nenu]

Can we have the system specs please?
What PSU was it running and what PSU have you replaced it with?

 

[Skrying]

Pentium D 820 stock
Asrock 775-Dual VSTA
1GB DDR Corsair Value
250GB Seagate HD IDE
6800 GS AGP
Antec 480W TruePower

PSU "replaced" (likely being returned since it didn't change the situation at all) by a Corsair 550W unit, forget which one. Motherboard replaced by a Asrock 4CoreDual-SATA2 that uses the same chipset (again, didn't change the issue). Video card replaced with a Gigabyte 8800GT 256MB PCIe (keeping, big upgrade, cheap on Newegg). None of these have changed what the system is doing. Have tried swapping the memory around and trying only one stick, changed nothing. The only thing not swapped out is the CPU, which I guess that could be it unless something weird could cause this.

 

[Nenu]

Just for kicks, try a different keyboard and mouse.
Also unplug any USB devices.

It does sound like your CPU is toast though.

 

[Skrying]

Just for kicks, try a different keyboard and mouse.
Also unplug any USB devices.

It does sound like your CPU is toast though.

It's a friend system, honestly I'm tired of just guessing. I've never seen this issue before with symptoms like this. I told her to have it shipped to me, I'll just swap in my own parts and see what the issue is. Shipping is expensive but better than $70 for a new CPU.