I had the same problem with my new i5-3570K / Asus P8Z77-V build. After much Googling I found out that you have to keep the voltages as low as possible while still running stable. I have mine at 4.3 GHz, offset +.040, PLL 1.7v. After playing around with voltages I was still seeing temps in the low 70s with a Hyper 212+ single fan. Saw a Corsair H100 for $100 and bought it on impulse (I have read a dozen positive reviews though). Now my max temps are about 60c fully loaded on high setting of IntelBurnTest (which seems to stress the CPU a lot more than the CPU burners in other programs). In the real world, like playing Dirt 3, or even encoding video, it rarely hits 50c. I like my temps low for reliability and longevity, and Corsair's flagship liquid cooling system does it better than anything else I know of (can't find any reviews yet on Thermaltake's Water 2.0 Extreme). I have no complaints at all about my H100; it's quiet and it opens up a lot of space in my case. I can now fill all my DIMM slots with fast RAM with tall heat spreaders, and I'm not bumping that huge heatsink any more every time I plug a wire in. Plus it just looks cool in my Corsair Carbide 400R case. Oh, and now I'm not afraid to try some higher overclocks knowing the heat is in check!