The overclocking potential is good. We managed to push the GPU 130MHz over the reference clocks (by increasing the voltege by available +0.037V) and let’s not forget about factory overclock, either. The memory also produced good results with a total 200MHz (effective 800MHz) overclock.
The cooler is now more important than ever, due to Boost 2.0 throttling and dynamic thermal management. Had it not been for the Phantom cooler, we probably would see a 8-percent performance boost.