Liquid-cooled G5 tower is a great computer and I have one in my studio
(dual 2Gigahertz). It is quieter than the G4 tower that it replaced.

However, it does have a variable fan ... it is usually pretty quiet
but it can get loud, as it spins faster the warmer it gets.

If it gets warm in your room you will probably want to put it in an
equipment closet or a separate room.

Only bummer I can think of is that one of the firewire ports is on the
front of the tower.

i use Protools and the G4 definitely feels sluggish compared to the G5
... would be hard to go back

--
Jordan