For the last 25 years, I've built, repaired, and maintained all sorts of PCs, laptops and servers. Hell, I've even repaired circuit boards. Today, I got stumped.

I'm working on an old PCs. Intel P4, 2gigs of PC2100 mem, on an ASUS motherboard. The PC kept shutting off after a 10 minutes. It was able to boot into Windows and seemed to work fine, then it completely shuts down. Usually it's a heat issue.

I blew out all the dust, reseated the memory and processor, removed unnecessary expansion cards, and it still happened. So, I replaced the power supply (new one is 430W) and reapplied some thermal grease on the CPU. Now, it powers on but won't POST. No beeps, no display... nothing. It just powers up, all the fans spin, and it shuts down in less than 2 mins.

I've went over the entire motherboard (back and front), looking for a popped capacitor or a burn mark... nothing. The MB is clean.

I'm stumped. For the amount of time I've spent on this old PC (that's worth about $50), I could have bought here a NEW computer!

Any bright ideas?

no display and no beeps is odd

I was going to say power supply but you swapped that

do you have an old vid card you can swap in to see if you get a display?

the video card was my next idea. I will give it a try tonight. I'm also trying to find a pair of PC-3200 mem to see if it's a memory issue. Pretty sure it's not, though.