PCs died and don't wake up

[taskufalafel]

Ok, my pc has worked so far flawlessly, until yesterday when it just shut itself down suddenly. I tried to put it back on, but when I press the power button, the power goes on for a second or 2, then it dies again. No error beeps, nothing. First I removed display card, no effect. Removed one or both RAMs, no difference. Removed CPU, still the same. Thought that maybe PSU is faulty, but at least some old P3-based system booted with it, so don't know about that. Is the motherboard gone or what can cause such behaviour?

When I took the motherboard out of the case to make sure there was no shortcuts, I noticed that the CPU-cooler's (the stock one, which came with the CPU) weight has made the board curved around the CPU-socket. The board was in the case vertically mounted (like in every typical tower case) with screws all around it. Can this cause some cuts in the conductors?

What makes this case funny (or even more aggravating) is that this is the second exactly same kind of breakdown in a month. Another PC refused to start and after some testing I experienced the same as I told above. I tried the PC2 with 2 different PSUs but no difference, and also without display card, memory and CPU.

Am I just unlucky or is there something else going on, because this is really confusing me.

HW:
AMD 64 3000+ (socket 754)
Abit NV8
2x Twinmos 512mb PC3200
Asus Geforce 7600GT (PCI-E)
Antec 350W PSU

HW of the second PC:
AMD Sempron 2800+ or 3000+ (don't remember) (socket 754)
Asus via-chipset based motherboard with agp-slot (don't remember this one either)
2x bulk 512mb ram
Geforce 6600
Antec 350W PSU

 

[drjman]

Sounds like you may have a short on the motherboard or case. I had the same problem before with a friends pc. I took out all of the components and set everything up on the kitchen table and was able to get it running outside the case. If you are brave, try that (i actually had it on directly on the glass table cover thingy). Don't worry about the board being bent a little, that happens with modern heat syncs. its probably the board or a short in the case/board.

Sounds like you have done adequate testing already, i would take all the components out and set them up to eliminate the case being the problem.

 

[taskufalafel]

I tried both ones out of the case on a non-conducting surface. Didn't help.