computer help please

So I've got these two computers here. Both AMD Athlon socket A flavor, circa 2001.

I need to get one of them working nicely so I can use EMC2 on it, a Linux based CNC controller that is packaged with Ubuntu 8.04 or 10.04.

When I got both computers they seemed to be mostly functional, albeit temperamental.. One of them I actually built for a friend back when I was in middle school, strangely enough.

Well, I'm at a loss. There are too many details to fit in a post that anyone would actually read, but suffice to say that after swapping lots of parts around to try to come up with the best combination for what I'm doing, both automatically shut off after running for about 5 seconds. Just enough time to get into BIOS settings and POOF.

I know computer related stuff is insane to try to diagnose over message boards but if anyone has any thoughts I would greatly appreciate them. I have them set up with only CPU/RAM/GPU and they still crash in BIOS. I've tried all sorts of RAM combinations and locations.

Haven't tried a rain dance but that's next

I do not believe it's an overheating failsafe, but it's acting like one.

i don't think they had a fan rpm failsafe on those, but perhaps on the later ones? i built a couple socket A machines around the same time, and still have one out in the garage. i think its a 1ghz athlon with whatever the top chipset mobo was at the time.

obvious question - have you checked the power supply?

also make sure the RAM you're using isn't too fast or too slow, we had one that didn't want to act right as well once, and it turned out that it could only run pc100 or 66 ram, pc133 was not compatible. or it could have been the other way around, it was a long time and many beers ago.

almost sounds like you're experiencing a brown-out on the circuit they are plugged into...

I keep the ram frequencies identical, and have the motherboard specs here to avoid mismatch, so I'm pretty sure that's not it.

I actually do not know how to check the power supply, although I do have an automotive style multimeter handy.

I seem to have the older machine sitting in BIOS with a single stick of RAM right now without issues. I'm going to futz around a bit. I'd rather use the newer one as the RAM is DDR333 and it's an XP 3000+. The older one is DDR266 and XP 1900+

It's amazing how little information there is online about these older custom setups these days. It was a chore just finding owners manuals for a few things.