Tweaktown if yeah want 4.0 base clock, ya need water cooling.
PS I am sitting down and listening to the video again, I posted the video earlier in this thread! Great to know people can't seem to get the info when its under their noses.
I totally disagree with that. A high end air cooler will allow 4 GHZ base clock. Obviously not a Coolermaster hyper 212 EVO. Try a Master Maker 8 or Noctua 15D, or a Thermalright Silver Arrow. No way those air coolers won't allow a 4.0 GHZ clock.