First post, by tony359
I have acquired an old AMD 386DX 40Mhz motherboard as "not working". It had battery damage. The keyboard was not working. I found some broken traces, fixed them and it works.
Except when I run DOOM. DOOM starts, I can start a game, it works for 1-60 seconds and then one of the following happens
1. the keyboard stops working but the video keeps moving
2. the whole PC freezes.
I tried the keyboard under Windows 3.1 and it works no problems. All keys. Anything I try (not much to be honest) works. Except Doom.
1. disabling cache
2. removing cache
3. swapping RAM
4. several different settings for the RAM
5. Installed a heatsink on the CPU
What puzzles me is that it only happens in DOOM.
Picture attached. I am not entirely sure but the photocopy of the manual I was sent with the MB says M921. I see a potential capacitor missing.
Any ideas? I have other pretty similar boards and they work with the same RAM.
Could you also recommend a test software I can use to "soak test" a board? Something that stresses it a bit?
My Youtube channel: https://www.youtube.com/channel/UCvxgGy-GkPY9RA9BcLTBaFQ