quiet HSF
The 900 is indeed an awesome heatsink - however... those long narrow passageways between all those fins require some decent pressure to get air to move all the way down to the "root" of each fin.
If you're looking for quiet, and so want to go with a slower-moving fan, take a look at the thermalright AX-7. That big block of aluminum under the fan motor conducts heat up and away from the copper block and out to the semi-radial fans. These heatsinks are only about $20.
I'd suggest setting one up with a panaflo 'L' 80mm fan, and using a fan rheostat (or PIC/voltage controller) and just keep turning the voltage down until you see temps start to rise or you just can't hear the fan anymore. I'm really surprised at how little aiflow the AX-7 needs.
You could try the quieter fan and voltage controller on the 900 - and that
probably would do a great job - and if not, you're only $20 away from a low-noise setup.
Oh - and I'm pretty sure someone here would give you $20 for the 900 you've got
Bob
PS (ob-water-cooling) If you're looking for a quiet
kit don't forget the
Innovatek kits. Their focus is on quiet.
PS2: Speaking of noise - are sure it's your HSF noise your parents object to? I'm
guessing that they aren't so PC-sophisticated that they're saying "Turn of that da***d heat sink fan!" - so your problem
could be your hard disks or case fans. If it's your
Mom who's unhappy, it could also be that your monitor is making a high pitched squeal that you can't hear (coil noise).
...just my thoughts - worth what you paid for 'em...