Regulating CPU Voltage

MdX MaxX · January 4, 2013

So for a year and a half I've had my i7-2600K stable at 4.6 GHz. I haven't had problems, but the behavior of the CPU voltage has always lingered in the back of my mind.

I have a Gigabyte Z68X-UD3H-B3 motherboard. In the BIOS I have Load-Line Calibration set at Level 6, the CPU Vcore at 1.36V, and the Frequency Multiplier at 46. Everything else related to clocks and stuff is Auto or default or whatever.

Now, in the OS, when I run Prime95, my CPU Vcore reads 1.36V. Which is good, that's what it's set to. When idle, however, the Vcore hovers around 1.40V-1.42V, sometimes reaching 1.45V. This doesn't make sense to me. Why does my mobo want to give the CPU more voltage when it's idle? Isn't that just wasteful?

My question is this: do I need to do anything about this? I'm sure 1.45V isn't hurting my CPU, but I'm sure energy savings could be had from it.

(Also, from my research on/experience with Load-Line Calibration/VDroop functions on this mobo, it seems that setting the Vcore to a certain value just kinda puts your actual Vcore in the ballpark, and it takes some arbitrary playing around with the Load-Line Calibration levels and Vcore to actually get the voltage you want. It's pretty much luck that my actually stabilizes at the voltage I have it set to while under load. I'm wondering why this is and what I can do to make this make more sense.)

ryan9298b2 · January 5, 2013

I would start by clearing your CMOS and then setting your overclock with the multiplier to what it was originally (4.6GHz), and then changing the voltage to 1.375v and leave everything else alone. I you need to change boot settings, that is fine, but the only things that need to be changed within the tweaker section is the actual voltage setting and the multiplier setting. See what your CPU Vcore is when you boot back into windows.

What software are you using, because it could be that it is inaccurate.