Hey guys

i was wondering if you know specific tools or a set of tools to test a vintage system's stability.
Currently I'm working on a DX4-100 (overdrive) build which is making me headaches because it more or less randomly freezes or crashes at games/sometimes doesn't boot win 3.11 properly and so on. even memtest86+ 4.00 sometimes starts and sometimes the screen stays blue with the "Memtest 86+ v4.00" string (plus sign blinking) in the upper left corner.
If memtest86+ 4.0 starts, it doesn't show any errors (let it run 2 passes at most which takes about 1-2hours).

i want to test for 100% stability:
- memory (guess memtest86+ 4.0 isn't so bad for that?)
- cpu
- disk (not so important, as I don't think there's a problem with that)
- vga card (vlb)

sometimes the system is stable at aggressive cache and memory timing settings, and sometimes memtest86+ doesn't even start with the slowest settings (I have a feeling that it starts to make problems when the pc warmed up a little). sometimes a second try (=reset by button) makes memtest86+ work.

I know it also might be the PSU, particularly because I've changed already the mainboard + vga card in that system and it behaved like that earlier... I've got plenty hardware to test with so if I figure that some part is working in another systems and in that one it is making trouble, I'll give the PSU a shot...

thanks!

edit: just tested with another PSU, same thing. memtest86+ hangs at start. I'll let the system cool down a little and if it works then, I'll know that it is some temperature related thing...