Ok, I'm thinking about getting a Thermalright SK6 heatsink because of how good everyone says it is. But I don't want the 7000 rpm fan. Now most of the time when i'm looking at fans they will rate it in cfm or mm. Which confuses me. Basically, I want a fan on that heatsink that provides pretty decent cooling for a 1.47 Ghz athlon XP (not overclocked) but is not loud like a 7000 rpm. Like maybe a 4,000 or so rpm fan. Any recommendations?