Normally I would’t recommend trying this, but in theory it wouldn’t do anything that installing a p54 wouldn’t already be doing. And the cpu should survive.
You would normally not do this for over volting reasons of the cpu, but as many others have pointed out, mmx chips always seem to survive it. (Though I don’t like it)
Anyway, disclaimers out of the way, at your own risk, you could bridge vcc2 and vcc3 on the fets with a wire if you are able to locate the proper fet legs/tabs. This will effectively be as if you installed a p54 chip. As far as the mobo is concerned.
You need to do it at a high current junction like the fets, as doing it at a single processor pin may burn the pin.
As far as the chip is conserned it will be as if you installed a pmmx in a socket 5 mobo.
The higher voltage reg will take the load and the lower voltage reg will just free wheel with the higher voltage on the output.
Anyway, it should boot up, the mmx chip will get hot as shit. (So heat sink it with fan and paste) But in theory it should work
many have run it this way (3.3v) for years, but I suggest you don’t keep it this way.
Many have also ran p54 chips on dual plane boards which make this same bridge I am suggesting.
If this does not boot up, then your problem isn’t voltage related. If it does, then your problem is vrm related. Vcc2 or vcc3
I still think you should confirm that your DVM is reading voltage correctly