Which is better?

I'm not entirely sure. This can explain it better than I can. I looked into water cooling for my rig, but decided it was more effort than I was willing to put in. It works really well though. If you can figure out how to put it together, it'll be much quiter than any fan you can get, and it'll cool better than a large majority of air coolers.

http://lifehacker.com/5940236/a-beginners-guide-to-water-cooling-your-computer