ATX/BTX ; Air/Water

[chillbill7]

I'm planning on building a new computer (sometime before summer) and have begun to investigate what components I want. I want the computer to be supersilent (I want to be able to have it always on in my bedroom, so I shouldn't be able to hear it at all at night), at least when it's not under heavy load (I'm not gonna be sleeping with Doom3 running anyway).
I was quite convinced that my next computer would be BTX, since it is designed to be a passive cooling solution, which would allow me to have less and smaller fans. The Problem is I haven't found any BTX components. Is the industry backing BTX at all (other than Intel, of course)? Which components have to be "BTX-compatible" (I suppose motherboard, case and PSU)? I also thought about using temperature-controlled fans, but they would have to be all over the computer (PSU, GPU, CPU, Case, ...) which would make it quite a difficult installation.
I could also forget about air cooling completely and go for a liquid (water?) cooling system, but it seems to me to be quite overkill (I don't plan on overclocking anything). Any suggestions?
By the way, I was thinking of getting something like an Athlon64 3800+ Winchester (socket 939, 90nm). The GPU will probably be an nVidia GeForce something (not sure yet). Thanks for any advice.

 

[The Boston Dangler]

BTX parts of all kinds are in extremely short supply. 2 lousy Intel boards, 3 or 4 cases, and no PCI express cards other than video.

The forums are full of recommendations for quiet and efficient cases. The Sonata is a popular choice, but I don't know if works well with a top shelf Athlon64. Stick with air cooling unless you're obsessed by the noise.

The new Athlons have some kind of heat management, don't they? Combined with a good temp probe / fan controller, this should keep your new rig quiet when only low power is needed.