The stock testing shows that Phanteks PH-TC90LS low profile CPU cooler delivers a 6 C improvement over the Intel box cooler that comes with the Core i7 2600K processor. By using its patented P.A.T.S and C.S.P.C. technologies the cooler solidly outperforms the box solution under load. When overclocked neither the box solution from Intel nor the PH-TC90LS were able to keep the thermals below 100 C; at that point they register a test failure. Overclocking at a lower threshold is possible and should be limited to roughly the clock speeds delivered with Intel`s Turbo Boost technology without any voltage tweaking."