Hello good afternoon, I write in case you could help me, the truth that I would appreciate it, I explain: I have an old motherboard Well a dinosaur is the dfi cb60-zx rev. Apparently it only accepts the Mendoza processor and of course at 66mhz , I don’t know if there would be a possibility of modifying the bios so that it accepted at least coppermine pentium III if the tualatin 1400 could be better clear, but at least that I could use the 100 or 133 bus because at 66 it is very slow and I don’t know if it could be done that boot by usb even 1.1 and that I detect hard drives of more than 20 gb I don’t know if something could be done, thanks for attending me, greetings … Hopefully something can be done 
Are you intending on doing a retro build or something?
Old Socket 370 Motherboards intended for Mendocino required adapters to run newer Coppermine and Tualatins due to some pinout and voltage differences. BIOS support is less important on those platforms, recall seeing weird things working with just adapters.
I know that there is a powerleap adapter to go from pga to fcppga but it is prohibitive the price is expensive and it is difficult to find it, so I thought that by modifying the bios I could put the cpu microcodes at least pentium coppermine and the voltage regulator cannot be put In the bios? The board that I know regulates the voltage automatically, but of course I don’t know if it could be modified to use the coppermine, thanks for answering