Currently I'm running 3Ghz with a Vcore on 1.275V. Using a Asus striker extreme with a nforce 680i chipset. I do not think that heat is a problem at this low overclock. Got a steady temperature under full load. Have tried almost every Vcore value between 1.275V-1.5V. I may need to raise the other voltages too but I don't know exactly how much to raise them, have been experimenting with no luck at all.