Random Non-booting/crashing problem

I've got a PC I'm try to get running, not sure what the problem is cuz I've never seen anything like it before. It will sometimes boot, and then crash at some point during the OS install, other times it will just power on (fans, HD, etc. start) but not boot. I've done everything I can think of to troubleshoot this one, but can't pin down the prob. Here's the config:

GA7DX mobo
1.3GHz Duron
250W Antec PS
2x256MB PC2100 Crucial
AIW Radeon 8500DV
SB Live! 5.1
3com NIC
IBM Deskstar 60GB
LG 40x CD
POS Case (just to hold the pieces together for now)

Any ideas would be helpful at this point.

That sounds like a power supply problem. Do you have a spare that you can put in there? No real surprise, a 250 is pretty marginal for any socket A AMD.

Even for the little I've got running in there? I think I've got a generic 300W around somewhere, but I thought Antec was a good make so the 250 would probably be about as good. If I have/can find the 300W I'll give it a shot.

Another quick thing you might try is to disconnect all unnecessary fans, drives, and leave out the sound card and NIC.

Yeah, I did that, it seemed to work better with less load, but one thing I did notice is the fan on the northbridge wasn't spinning. Not sure if that was an issue, but once I gave it a nudge immediately after hitting the power button it spun up and the system booted and ran stable enough to finish installing the OS. Could be an indication of low voltage? I haven't found a bigger PS yet, but if I do I'll give it a shot. Hopefully that is the issue rather than a faulty component.

edit: Just got it to boot again and loaded MBM 5. My +5 is down at 4.35. Seems low to me. That's probably the problem.

If your 5v is that low, I'd say you have a PSU problem. Sounds as if the northbridge fan was unable to spin up from a lack of juice.

Yeah, it was sitting there wiggling like it wanted to go, but didn't have enough to get started. I finally found a 300W in an old PII system and swapped it with the 250 and now they're both running just fine. My 5V is still a little low at 4.81 idle, 4.73 under load, but the system is stable and isn't going to be used all that much anyway.