Computer experts, please give me your advise

[TedR719]

I have a custom built comptuer and was having trouble with the computer just shutting down and restarting. About 6 months back I bought a new CPU fan and the problem was solved but only for like a month or so and then it came back.

So just recently I had the computer dusted out, since it was filthy and backed up my info on cd's. I had someone attempting to repair some lost files in windows (like notepad) and after a restart now I get nothing on my screen.

There is a signal to my monitor cause when I unplugged from the motherboard it shows the info floating on the screen. So its not the monitor, but when I hit the power button to the computer it will fire up and the mouse will light up but nothing on my screen.

Now from what I was told it has to been a hardware failure since the comptuer would just restart out of no where. My question is what piece of hardware could it be, I'm thinking it could be the motherboard, but I'm no expert on this so I thought I would asked before throwing money at parts :)

[STIBungy]

Could be memory. Take that out and reseat it.

[CT9A]

Also try reseating your video card.

[LeonZ]

Could be the memory, like Bungy said but could be a number of things. If you can, take out the hard drive and put it into another machine. If it boots up fine, hard drive is not the problem, unless it's a software issue. Could be a video card as well... If you have a spare video card, try that. When you turn on the computer, does it make any sounds during the power-on-self-test? Chances are if it's a basic hardware issue like video or memory, it would beep. If the hard drive is fine, try taking out peripherals like CD-burner and PCI cards to see if the computer would turn on without those devices...

[wild.irish]

yep, strip it down to the point where you only have motherboard with cpu and memory, and a video (if it's not on the motherboard). if you don't even see bios information, then it's either memory or mb. why did you change cpu fan in the first place? if it was restarting like crazy, it could be overheating, and if you got a new fan, maybe it still was insufficient and you fried something?

[Nightfall]

I would lean towards an overheating issue because you replaced your HSF and it fixed it for a little while. What did you use between the heat sink and the processor? Did the heat sink you bought come with a TIM on it already? I would take your heat sink off, clean it up, clean up the processor and go buy some Artic Silver. You only need a thin layer between the CPU and the HSF so don't gob it on.

One other possibility could be a weak power supply. What is in your PC as far as hardware? What power supply are you using?