I've used a Tuniq Tower 120 in my 900, and it did quite well, but for the money it's hard to beat the Arctic Cooler Freezer Pro 7. I ordered one for a client this weekend from newegg and it was less than $20 now. It does as good or a couple degrees better on my E8400 than the Tuniq did, and it's lighter and puts much less stress on your motherboard. It's not a real flashy unit like some of the Zalman coolers, but I like it a lot.