I'm currently running:
i5 3570k Ivy Bridge @ 4.2Ghz
ASUS P8Z77-V LX
Nvidia GeForce 460
When I load up CPU-Z, I notice that my Core Voltage is bouncing around between 0.800 Volts and about 1.2 Volts idling in Stormwind, and my Clock Speed going between 1.6 Ghz when running basic applications, and 4.2 Ghz when I'm running WoW.
Is this erratic changing normal, a friend told me it was just my mobo / computer trying to conserve power, however I'm unsure.