Reply 27660 of 29081, by NHVintage
Thanks for the PCChips suggestions, all. I tried the chip press and no dice on any of them (or any combo of chips being pressed). I don't have an EEPROM reader or an oscilloscope, so I can't check with those. I was going to try swapping BIOS chips with another board (it wouldn't boot but it would do SOMETHING I figure, letting me know that's the problem) but sadly, I don't have another board with that same chip type. Naturally.
I decided to pull the BIOS chip and reseat it to see if there was an issue there (the contacts are pretty clean both on the socket and the chip) and while I had the chip out I powered up and noted the activity (such as it was) on my diag card was unchanged, so that suggests to me a bios issue. I noticed it was easier than expected to take the chip from the socket, suggesting someone maybe swapped chips or otherwise played with it, possibly. So, I guess its time to get an EEPROM reader. 😀
EDIT: Anyone got a suggestion for a good EEPROM reader for a windows 10-11 machine? They ain't cheap and would prefer to get one that someone's actually used. Thanks!