After recently buying a noctua nh d-14 for my i7 2600k i had a little play with it over the weekend on the auto voltage settings, setting down to set a decent stable clock manually i began to set the vcore manually but its never working properly either it doesnt boot into windows or when it does boot into windows only 1 core seems to be working or being recognised. the motherboard is an evga z68 ftw, i have tried a variety of voltages etc but no joy. whenever i set it back to auto voltage it works pefect again, its got the latest bios which i flashed again today just to make sure but its still not working. ive been in touch with evga and the guy said i should have a look under the chipset heatsink to see if it has p67 or z68 printed somewhere ????