Hmm, well, the problem must lie elsewhere. For the moment, leave your vcore at "normal" and use the appropriate offset (-0.015?) to bring it back to your original, stable voltage.
That screenshot at the top of the page suggests you can alter the LLC level. You could try lowering it and see if it makes any difference.
Other than that, you could tinker with the PLL overvoltage and Memory Performance Enhance settings.