i have the intel 3570k which stock at 3.4 GHZ i have it at 4.0 right now i have a cpu tester and when its at 100 cpu usage it gets to temps around 68 Celsius and soon as it hits that i stop what is a stable clock i am using a cooler master hyper N520 when its idling it drops it down to like 1.2 when it is idling for power saving and the temp is usually 30c to 37 Celsius let me know what you think if i can or should go any higher.