I haven't yet figured out exactly what the problem is, but I suspect something fairly brainy is involved, such as the cpu, motherboard, or ram.
I've managed to get it into a seemingly stable state, but I did a number of things at once:
- stop using binary nvidia driver
- changed ram modules to one i had laying around
- stopped using ram slot #2
- stopped using ram slot #3
- slowed down the FSB
- turned off a bunch of stuff in the bios
So I'm not exactly sure which of these has made things better, and I'm pretty lazy about trying to figure out which, especially since figuring out which requires (1) shutting the machine down and (2) intentionally breaking it.
But even though it's seemingly stable now, it would be nice to get new hardware so that I can be more confident. Also, quiet and lower power would be nice. I'm learning about mini-itx stuff, which could well be the answer.
I shall post ideas for new hardware here as they formulate.