stable as a rock @ 4.6, with my small water cooler i push to 4.8 , only keep it for half hour playing bf3 on ultra settings , gets hot, need a real good water cooler to be stable any higher, at any rate it beats the 4.5 posted above easily and its lame to say its not a better chip when it is, maybe not a super jump up but better still.
if your amd then thats your choice, just don't think you can rate a chip you don't own.
spend 200.00 plus on water cooler then clock it above 4.8, many people have posted 5.0 and above hence why i bough this chip "I7 4770k".