I had the same question and answer wasn't received ( I used only 1 program simultaneously, but results were different in all apps: AI shows one, CPU-Z\HWMonitor shows another - and these results can't be due to BIOS voltage border), so this question is open on my opinion.
I had this same issue and I see the fix mentioned here ocassionally, but not consistently. I am running 4.5 and 1.25v, but before I made this change, I was consistently running hot and in the 1.35-1.38 range.
In the bios, look for the CPU Load-Line Calibration option. It defaults to Level 7. i changed mine to Level 5 at first and since have adjusted it to Level 4.
More info Here: http://www.overclockers.com/load-line-calibration/
Don't disable it, but lowering it will likely stabilize your voltage in addition to your OC.