The i7 2600K at 4.4 GHz with 1.35 volts pumping through it is not a cool CPU and can easily overwhelm coolers that aren't up to the job. Even at idle, the coolers start to separate themselves by their relative performance, since all power-saving measures are disabled. Once I fired up Prime95, it became obvious which coolers could handle the heat and which could not. The new Water 2.0 Extreme matches the performance of the Corsair H100, albeit with less noise. Just behind the water coolers and ahead of the rest of the field, is the surprisingly good DEEPCOOL Neptwin. The TPC 812 and Ice Blade Pro V2.0 are on even ground here, but have jumped into the uncomfortable 80+C range that many wish to avoid like the plague. Again, trailing the rear of the pack is the NH-L12 low-profile cooler that just can't handle the heat that the 2600K can dish out at these speeds and voltages. It isn't quite in to dangerous territory, but at 87C in a relatively cool room, it is a lot higher than I'd like my CPU to be sitting for extended periods of time.