I have a Q6600 running at 1.5v 24/7 and the H50 keeps it down to 33-36 idle and doesnt go above 60 playing games like ut3.
So even for overclocking its pretty decent. And this is with PWM controlled fans so at idle its super quiet. I did replace the stock fan for 2x vipers.
Dont believe all the H50 bashing around here, yes its not proper watercooling, yes if you buy a heatsink the size of your motherboard it will be better aircooling, but this is easy to install, needs near no maintenance, and performs well without being so noisy.