Alpha PAL8045 was central to silencing that athlon rig I had. Back in the day, PWM and voltage varying to adjust RPM of fan were not in the cards with many boards. This was very close to start of implementing the quiet features to the boards in the near future, but mine does not have these necessary features, and my hearing is not that good, this means extra noise is not welcomed. Thus, made a voltage adjustable card and this Alpha PAL8045 heatsink with fan on low and other fans as well, allowed me to hear the ambient sounds that I wanted to hear instead of that PC drowning this out.
Cheers,
Great Northern aka Canada.