I recently built a system with an i7 6700k with a cooler master hyper 212x. I managed to oc up to 4.4ghz with a vcore of 1.2v, stable run test thru aida64 for 12 hours. However, when i tried to go 4.5 with 1.3v the system cant be stable. So my qustion is do i need a better cpu cooler so i can get past 1.3v? Because whenever i up my voltage to past 1.3 my system always crashes. Is it the cooler or i have a bad cpu chip? Any response will be much appreciated. Thanks.