The Zerotherm Nirvana NV120 is a fantastic cooler that outperforms much of the competition between the very quiet to silent fan lower speeds. And, although it is technically the best performing heatsink we have seen to date, we'd never recommend using it at full speed.

On the other hand, the Thermalright Ultra 120 eXtreme is a product that really does deserve its eXtreme branding and the hype surrounding this product is deserved. Without a doubt, it is /the/ CPU cooler to own at the moment and it's the next best thing you're going to get without plunging into the realms of watercooling -- even though it's very expensive for an air cooler, it's still good value in the grand scheme of things. But a 3?C difference over that of the next best cooler we'd buy might not be worth the significant extra investment to some people.

Its installation might be awkward and the fan mounting it just atrocious, but once that momentary stress is passed it doesn't matter because its build quality is fantastic and you'll have a truly silent setup that can handle just about /anything/ you'll throw at it. If you're looking for the ultimate CPU cooler, make it your mission to own the Thermalright Ultra 120 eXtreme.