Stalls at partial post

Recommended by Wim's BIOS...

I forgot to mention that I did have the bios chip out and attempted to boot the board with another chip. I think this may have been what fixed it.
Couple of years ago, before I dared to flash a bios, I had two Asus 430FX motherboards, Pentium 75 to 133 vintage, of different Rev. numbers, both with problems. I was able to get one of them working after trying the bios chip from the other one in it. It didn't work properly with the wrong chip, but when I put its original back in it worked.
It is my theory that swapping chips can sometimes jog an "almost working" bios back into shape.