I have to disagree with Db51
"A 'silent' fan and 'silent 'power supply and 'silent' harddrive might be quiet enough for the average gamer who doesn't want to be bothered by noise, but if you're gonna use your pc as a DAW, you should put it in the closet. "
I kitted out my rackmount system with the silent fans, power supply and i didn't even need to get the hard disk 'cover' --- It's more than quiet enough. Look at the computers built by carillion. They are used in loads of studio's, studio's which don't necassarily have the isolation boxes.
Admittedly, standard PC boxes (from high street retailers) are shite for noise. My last PC sounded like a boeng 747 when it started up. I eventually found that it was the CPU fan that was the loudest.
The best Hard Disks I have found (and the quietest) are the IBM 60GXP drives. You literally can't hear them. but don't put them in a silentdrive enclosure... they get really hot.
Also, if your pretty handy with a soldering iron, you could put a variable resistor in front of the fans, so that you could slow the fans down when recording. Or, even kinkier.... head over to ucapps.de
A guy has designed a circuit that switches things on and off with midi - He can even switch his kettle on and off!!! you could set it up, so that when you press ' record' the fans slow down!
just an idea *pipe dream*
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