So I've been overclocking my e6300 for more than a year now from 1.8ghz stock to 2.4ghz. I've left everything on AUTO in the bios (p5b mobo) except fsb frequency obviously and all was good. Now, I've decided to play with Vcore to lower the heat generation.
On stock it's 1.272V (1.8Ghz)
Overclocked it's 1.36V (2.4Ghz).
So as a first step I've lowered it to 1.3V. However, instead it just decided to lower itself to 1.216V. Bios, Cpu-Z and speedfan all show 1.216V and not 1.3V. And the fucker is also stable so far with prime running for more than a hour on vcore lower than stock's!
Anyone knows that's going on? I've checked and it holds the 2.4 freq steadily, ie no power
saving or anything to explain the vcore voltage. 
i7 6700k @ 4.4 GHZ, 2060s, 16 GB RAM, SSD, Windows 10x64.