ASUS P8P67 PRO, Vcore help

[russelljg]

I've recently got my new system and am trying to find a good stable overclock.

Basic details as follows;

i5-2500k
ASUS P8P67 Pro (3.0)
Corsair TX850
Vertex3 SSD
GTX 560Ti

I've got it stable at 4.4 (with PLL overvoltage off so it'll wake from sleep) but it will BSOD at 4.5...fair enough.). Temps get to 60-62c.

Vcore is manually set at 1.39.

My (basic ) question is as follows;

I booted the machine at 4.4 and started up Prime95 and CPU-Z, whilst Prime95 was running CPU-Z reported CPU voltage as c1.32.

I then stopped prime95 after a few minutes and started up a 3D game (RIFT as it happens), at that point CPU-Z starts showing CPU Voltage at c1.39.

So the simple (and probably noob) question is, if Prime 95 is driving the CPU at 100% and voltage shows as 1.32 why does it change to 1.39 at lower load when I start gaming ?

Thanks in advance.

 

[tnt3k]

did you set load line calibration?

http://www.bit-tech.net/hardware/cpus/2011/01/07/how-to-overclock-the-intel-core-i5-2500k/3

this guide seems pretty helpful