Seems to me a lot of people tend to talk more about there cpu, than what HS and Fan they get.
I recently got 2 of these for 2 of my work rigs here at home and there absolutely excellent, extremely silent. A little big tho, ( so check if you wanna get one ) but thats fine by me, what you pay for for silence you pay for in size when it comes to cooling IMHO... But out of all the HS's ive ever had with a fan, this is the best one. Comes with a controller too, so you can wack it up if you want to. Down side for me is the silly green led on it, which you cant get rid of, but no biggy. I can only hear my HD when im caining it. There might be better ones, but what the hey.
CNPS9500-AM2
Ive also got one of these, which ive had for about 3 years, it isnt too bad either. No whirring what so ever.
AC Freezer Pro
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Not really looking for spec comparisons, just wondered what others have fitted?