Water cooling a PC  was not something that I had considered before, as it seemed a bit counter-intuitive to have electricity, and flowing water in the same box.

A point you may wish to consider in your studio is that any noise from your PC fans will be picked up by the studio microphones, and be recorded along with the voices or instruments, if the computer is in the same room. This may not be unacceptably loud, but if it is deemed to be so, then there are three alternatives, that I can see:-

A) Site the PC outside of the studio area, as the BBC, and other studios do, or at least as far as possible away from the microphones. Most high-end organizations have a separate server/racks room. The only trouble is, it can get very expensive with many long cable runs between the two areas.
B) Use a noise removal tool, such as adobe audition’s which is included in the software, and works very effectively for static noises like PC fans and A/C, with a very slight trade-off in sound quality, as the software inevitably removes some of the useful audio data and needs to be run after every recording, which can take time.
C) Take the fans out and water-cool the PC. (This is what I decided to do in my own studio, as I don’t have a separate server room). This keeps the PC dead quiet, and very cool, and cost something in the region of £350.00 to install. I got my water-cooling kit from here:-
http://specialtech.co.uk/
(I have no connections or business affiliations with this company however)

It feels slightly dangerous filling your computer’s reservoir tank with fresh water, but I’ve had my system running continuously now for 9 months, without a problem. The PC runs more or less at room temperature now, so the processor will probably last forever! Gamers like to use coloured, or even pearlescent dyes in their cooling systems, but it’s just for show, and it’ll work fine without. All-in all, water-cooling my PC  was a simple task, and well worth doing just for the blissful silence!

Martyn Baker is a BBC-trained sound engineer and studio owner/designer, currently working for BBC news, various freelance clients such as Aljazeera English TV news, and has recently launched his yougig service for musicians in the UK to promote themselves with high quality live audio & HD video recordings. http://MobileRecordingStudioUK.com