Reply 20 of 21, by VicBond007
Necro-posting because this came up in a Google search for me, so others might stumble on this thread as well.
I have a GA-5AX revision 3.0 board.
The official latest F4 BIOS on Gigabyte's site works for PCBs 3.0, 4.1, and 5.x. CRC32 of the BIOS file 5AX.F4 is 59917B47.
https://www.gigabyte.com/Motherboard/GA-5AX-r … support-dl-bios
You'll need a bootable machine to flash the BIOS, so get a cheap old K6-2 or something first.
After updating, it absolutely works with AMD K6-III+ (don't forget to change your voltage!). I have a K6-III+ 450 in it now. Works great with setmul to change multipliers on the fly, both up and down.
Note that the MANUAL for version 5.2 is very different than 3.0. Jumpers specifically, so follow the notation printed on the board. RIP: my old CPU.