Firstly i would like to say that the other person who has reviewed this is a complete and utter FOOL! I installed this on a AM3 socket with a AMD Phenom II x4 955 Black Edition and it reduced the idle temprature of my cpu from about 44C to about 35C. It was fairly easy to install with very clear instructions however I did find it a bit fiddley to mount the heat sync and also plug the PWM cable in, but this is due to my small case. It came with pre applied MX-2 thermal paste however I replaced this with Arctic Silver 5. It's extramly quiet however you CAN hear it. It is NOT completely silent.
This was my first ever installation of such a substantial component and I have to say it made the process very straight forward and easy to understand. I'd just like to point out that I'm only 16. Just shows how simlpe it was. Highly recommended for everyone from people who want a silent PC to MILD overclockers.