If you have the space, just get one of these MONSTERS!
http://www.comairrotron.com/dcfans/MajorDC.htm
Size: 6.75" x 5.92" x 2.00" deep
(171.5mm x 150.4mm x 50.8mm)
300CFM! I found a couple at an electronics liquidation store for only $6.50... I'm running it at around 8volts and it still puts out 157CFM! It's almost silent. And the bearings are nice too.
I was thinking that if you have the room and a nice shroud, you could get a blower-fan and just make a bend for the air to flow towards the rest of your system cards. Blowers are usually the most silent of fans. Good luck
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XP 1600+ AGOIA-Y (GreenLabel, UNLOCKED!@/ NF7-S 2.0/ PC 2700 DDR
10.5*172FSB(1806/ 1991 high), Vcore 1.792...@84.95Watts
--86' Chevette Heater Core
--1/2" Vinyl tubes
--Via1300-Stealth Mod(QUIET!)
---Home made copper-tube block
---PVC small internal res