InsideHW.com has compared performances of 9 CPU coolers.

We all like that our rigs are well taken care of and safe. Components inside the chassis are emitting heat and good cooling system will guarantee longevity and pristine condition of system as a whole. Most of us start thinking about better CPU cooler when summer heats has already arrived. A lot of users keep their rigs overclocked 24/7 and this can be a problem when temperatures during summer months raise. This can result in overheating of some components and in worst case scenario some of those components can be irretrievably damaged. In most cases CPU is the biggest problem, because default (box) coolers that came with CPUs are not too efficient. So, what cooler to choose? We are offering you a little bit longer answer to that question, but we reckon that it will be worth reading.

9-Way CPU Coolers Roundup