Well, I couldn't deal with the noise from my retail HSF. I had the retail Intel one that ships with the 3.2c chips - copper base, aluminum fins hooked up to my Intel 875 mobo variable-speed CPU fan header. When it would get warm in the room and the fan RPM's got above 4800 or so, the thing was just too loud. It was louder than my Dual AMD system with two 42CFm Sunon fans.
Swapped out out for the Zalman and now my CPU temps are 6-8 degrees lower, fan RPM's at 2375 (full blast), and I can't hear it above my case fans.

Swapped out out for the Zalman and now my CPU temps are 6-8 degrees lower, fan RPM's at 2375 (full blast), and I can't hear it above my case fans.