Intermittent startup problems

[onesNzeros]

I have an older PC which I had built back in late '04. Recently I've started having occasional problems getting the computer to power on. Basically, I can see the red light on the motherboard (a DFI LanParty UT 250Gb nForce3 board) near the RAM when my power supply is turned on, but pressing the power button on the front of the case, or the one on the motherboard itself has absolutely no effect. After a while I've been able to get it to power on in each case, but I'm just waiting for the day to come when I can't.

The problem usually happens after I've shut down the PC down using the power button (if there was a problem that forced me to do so) or if the power supply has been turned off after the PC went through a normal soft shutdown. As long as I don't actually turn off the power supply when the PC has shut down, I usually have no problem getting it to turn back on.

Any idea what could be causing this? My fear is that it's the motherboard that's failing, which would ultimately require me to basically build a whole new PC since everything I have plugged into it is virtually obsolete at this point.

What do you guys think?

 

[ViRGE]

The motherboard and the power supply are both possible culprits. You may want to try another PS if you have one spare.

 

[Old Hippie]

The little red light doesn't mean your entire PS is working properly.

I'd be swapping to a known good PS.

 

[onesNzeros]

Well, I like the power supply answer a little better, but without gutting a family member's computer to test my own, the only other PSU I have available to test with is only a 200-watt from my now very old Dell. To be safe, I suppose I could swap the much less power-hungry video card out from that PC as well and see what happens, but that wouldn't be a really fun project, assuming the old PSU even has all the necessary power connectors. My only alternative (short of a visit to a repair shop :roll would be to take a gamble and order another PSU for maybe $75 and see if it fixes the problem. Might have to bite the bullet and try that, but I don't like troubleshooting by trial-and-error purchases. That can get pricey...

Any other thoughts or suggestions as I mull this over?

 

[Old Hippie]

You could troubleshoot with a multimeter to eliminate the PS.