I have a MSI P35 NEO-F with bios v1.6, Q6600 G0. Regardless of what I set the VCore voltage to in the bios, the bios, CPU-Z, speedfan and MSI DualCore all show 1.36 - 1.34 idle and and drops under cpu usage.
You may need to disable intel's C1E throttling, which will control your voltages by default. I have a MSI board too, and for some reason, the option only becomes available when you hit f4 at the main bios screen.
Ok I tried both ways, F4 and alt+F4 and F4 gives a menu option called power users that has 3 settings, CPUC1k0 Skew (0-1400ps) and CPUC1k1 Skew (0-1400ps) and Dram Channel Controller (disabled/enabled) in the Freq/Volt Control section of the bios. (I have no idea what those are lol)
If I use Dual Core (MSI) then I can set the voltage down and it will stay until I reboot then it goes right back to the 1.34 to 1.36 range.