Problem: I was able to Run this rig with a 4.7GHz OC at 1.435v, 58C under load, for a few months. Now I cant even raise the voltage by itself (no multiplier change) without having the overclock fail. Nor can I raise the multiplier by itself to 4.2GHz (no voltage change) without having the overclock fail. Goes without saying my OC fails if I raise both voltage and multiplier. The rig runs just fine at default settings.... Thanks for the help.
Can I ask what you did within your BIOS? like how you oc'd after you crashed?
and this is just a possibility, Maybe your CPU is not getting enough POWER, that one of your railings went bad since it can run at stock and not at OC.
After the crashes started I did tests with small overclocks with no success. (NOTE: I would always turn off the extra cool n quite type features before any overclock.) Raising just the multiplier to an overclock of 4.2GHz with no voltage change - No success. Raising just the voltage to 1.45 with no overclock - No success. And many other combinations of voltage/multiplier.
Its a single 12v line. Maybe its having a hard time handling higher voltage or inrush from the cpu. Want to rule out all other things before having to buy a 1000w PSU. You would think 775w @ 65 amps would be enough lol.