I used to have a pretty smooth running 4.4ghz OC on my i5-3570k running on an Asus p8z77-v pro and the temps were fine, 80degrees max (I use an H100i water cooler as I don't know how to set up my own loop and wouldn't trust myself to try). Anyways, in the heat of the Summer here I restored my settings to the defaults hoping to keep my home a little cooler, however, after trying to get my OC back just yesterday, I can reach 80-90degrees from just playing Grand Theft Auto and stress testing gets me to 100degrees in a hot flash! The only difference I have noticed in the behaviour of my PC is that when I used to set the voltage @ 1.250V it would reach a MAXIMUM of that but would typically run at a lower voltage until I really needed the kick, but now it constantly runs at 1.250V* which I would guess is the killer. I'm not an extremely experienced Overclocker so I'm not sure what else I could mention but if anyone needed more information then it could be provided.
*Note that all past and present voltage recordings were taken using CPU-Z
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