Still fiddling with this and nothing special in the design -- just quiet components. Apologize for the quality of the pics, when I finish I'll try to get some good ones.
Intel 2.4Ghz Northwood w/ one of the original Zalman 7000 AlCu sinks @ 5v
Abit IS7 motherboard with the northbridge fan replaced with a Zalman NB47J passive sink glued on
Toshiba MK8025GAS 80gb notebook drive
NEC 2510a DVD burner (slowed down with Nero drivespeed)
Sapphire Ultimate Radeon 9600xt
Hauppauge Win-TV PVR 250mce
M-Audio Audiophile 2496
Netgear gigabit lan card
Antec SL350s PSU modded with a Japanaflo 80mm L1A
Japanaflo 80mm M1A-BX @ 5v (exhaust)
all wrapped up in a Kanam Accent HT-400b htpc case
Airflow in this case is very good with an intake in the bottom under the optical drive cage as well as intakes along either side (sorry, no pic of the sides yet). Full load (FAH), temps stabiliz around 48c (ambient 23c).
The box sits in an enclosed entertainment center with an opening in the back for the exhaust) & runs 24/7.
System is inaudible with the entertainment center door closed. With the door open, you can hear the exhaust fan slightly (from cd changing distance -- a little less than 1m.
All in all, a success. As I tweak, I'll update...