After much messing around and trying different settings, here are my stable settings (i5 2500K @ 4.5 Ghz and a voltage of 1.288v under load, I am at 1600 Mhz and .944v at idle) . I don't know if these will work for everyone but they did for me. I realize I went against some of the conventional wisdom regarding pll voltage settings,phase control,current capability and load line etc., however with some of the "standard" OC settings I was very unstable. So, here is my ASUS z68 bios settings:
Hope this helps some people. Good Luck.
** Am running1 top exhaust fan, 1 rear exhaust fan, 1 front intake fan, 1 side intake fan and Thermalright Venomous XR-T air cooler, so temps. are good: @ 27ºC (or cooler) at idle, @ 45ºC playing games on maximum settings, and @61ºC using intel burn test, OCCT, Prime95 or other stress tests.Edited by TrueLies64 - 1/18/12 at 7:14pm