Am I disappointed in the overclocking headroom available from this processor. Not in the least! With the insane speeds being offered up by the dual core variants, I was still searching for a bit more than the 3.7GHz I was able to pull from this quad core processor. But even though I was expecting more, a greater than 1 GHz overclock is nothing to laugh at. The clockspeed increase was also done with a relatively low 1.36 volts to the processor. Much less than I have needed with both my Q6600 and QX9770s to gain the maximum core speed. Temperatures were, for the most part, kept in check throughout the testing. 64 degrees Celsius under load was the highest temperature I saw on air cooling during my stability testing with Prime 95. With better cooling, could the max overclock be increased? Probably, but the vast majority of users will be on air, so that's where I spent my time testing.

http://www.overclockersclub.com/reviews/intel_q9450/