There's CPU voltage and there's the addition of offset voltages with LLC, so I tend to agree as described that your 'real' CPU voltage is indeed spiking.
Unless you're having non-OS related issues updating the BIOS has its risks, so its your call. Use only a BIOS level flash i.e. Q-Flash to update your BIOS.
The voltages in your BIOS don't show the correct voltages when your CPU is stressed.
Hmmm, I thought LLC was supposed to keep your CPU voltages "even" as a protection from Vdroop, I didn't think it was supposed to "spike" it. Do you suggest disabling it altogether for overclocking purposes or should I just drop the voltage in the BIOS down till it reads where I want it?