pc problem. help needed!

[sharky]

hi guys! i have a probelm with my pc.

at random times it locks totally up. it is not related to the operating system since it happens even inside the bios.

i tried almost everything and from my tests i can for sure exclude:

GPU
Sound card
Hard drives
CPU
RAM

the temperatures monitored from the bios are all ok. everest doesnt show any anomaly too. the only thing i see strange is the nforce 680i SLI chip on my mobo. the heatsink is very very hot. i have a single gpu, so the chip shouldnt be too much under load. i did not overclock anything, the mobo worked just fine for over 1.5 years.

tonight i will measure the heatsink temperature. i can not touch it because it hurts after 4/5 secs. as a pure guess i would say its around 55/60 °C.

any hint on your end? im going crazy.

[Tril]

Did you always have trouble with this computer or is this problem recent?
Did you change any hardware recently?

[sharky]

nope, didnt have problems before and didnt change any hardware.

im going crazy on this.

any suggestion is welcome. im worried that i have to replace the mother board or the psu.

[cybereality]

Sounds like it could be an issue with the motherboard but its hard to say. I guess it could be the PSU as well. I would probably update the firmware on the mobo and try to rule that out before anything else. Thats a weird issue though.

[Neil]

I'm betting it's the PSU.

If you get BSOD, then I would say memory. If it's just a random freeze, PSU.

Regards,
Neil

[Tril]

I've had a computer randomly lock up but it was a different situation from yours. When I first built it, the BIOS was using an old version that had compatibility issues with RAM. It would randomly crash while installing more than one stick of RAM or while installing Windows while using one stick of RAM. A BIOS update fixed it. This solution does not apply to you since the computer worked before.

A problem with the RAM can make the computer lock-up but I think that RAM is usually pretty reliable. If you have a RAM problem, it's more likely that it's caused by a faulty motherboard rather than the RAM itself..

I've had a computer lock-up because of a broken motherboard. It had a problem with bad capacitors and it ran for too long at a high temperature (Prescott CPU that always ran very hot) which helped break something faster.

I guess a PSU problem could also cause problems but I don't think it ever happened to me. If you've got another one, it's easy to swap the PSU temporarily to see if it fixes the problem.

[sharky]

hi guys!

here are some more clues to find the problem:

if i run the memory test (just as application to avoid loading windows, memories are fine, tested them several times) then suddenly it locks up. BUT there is a red "+" at the top left that keeps blinking even if teh pc is locked up. in order to be able to blink it needs the GPU and the GPU. so we can safely exclude those. does somebody know if the mother board is needed too (COMPLETELY working i mean) to overcoem this simple task? i opened the PSU there are no blowing capacitors, and even on the mother board there aren't. the issue is not temperature related since i cooled it down a lot, and it happens also on cold pc now. hardrives have both been unplugged and the problem persists. ram have been tested, replaced, switched, still problem... i am goin crazy..

thnx

igor

[sharky]

pc works.. it was the psu..

thanks for the help guys!