Finally got around to test boards and one of them is SiS 551x based pentium socket 5 has corrupted bios firmware, saying bios checksum is bad. Need to find time to make new fresh firmware for the P/I-P55SP4.
Update: Board is not doing too well after refreshing the bios, keep saying 8MB no matter SIMMs I use and detects no cache with either 32k x 8 or 64k x 8 chips. Jumpers set correctly. Only thing is CMOS batteries are all flat. I searched my stock of boards with battery coins and two I found is also flat!
Ordered fresh Intel flash chips (NOS) and 10 pack of CR2032 cells.
Really wanted Asus P/I-P55SP4 to be set up with async 512K cache but this board is not going anywhere yet until I straighten out the no cache detected and memory stuck at 8MB no matter SIMMs I use, using pentium 133 CPU. Future plan is put together a slow combination of async, winchip for old DOS machines.
Looks like my compaq computers are winning so far, they simply keep working.
Cheers,
Great Northern aka Canada.