Yes, it is exactly what I want to build: a dedicated music server.
I will take a mini-itx motherboard with Atom CPU (Intel D510MO, or Jetway JNC96FL) with 12 V DC input, so it is easy to build an external linear power supply. No fan at all on the motherboard, and no videocard with fan, the videocard is integrated on the motherboard. And no fan in the case, I use the "natural chimney effect" (mounting the motherboard vertically).
The OS wil be on a small SSD, and the music files on a SATA or external USB (900 Gigabytes of files in FLAC !!!).
For the soundcard I use a PCI risercard, so the soundcard will be outside of the motherboard. And furthermore I can shield it without problems.
The only negative point is that I have to use Windows XP. Hundred of back services which use CPU activity for nothing !! It is possible to tweak it a little, but not as much as Linux !
I wanted to use Linux, but with the 9632 card, under Linux, it is impossible to switch automatically the sample rate on the fly when listening to files with different sample rates, if you want to make bitperfect playback (with MPD for example).
Sad that the RME team doesn't want to deal with Linux !!
Anyway, with Windows and Foobar 2000 (with Kernel Streaming or ASIO) I hope the sound quality will be good enough..........