I'm buying the 1.42 Powermac w/ the 20" Cinema Display and 9700 Pro card ... now I need to consider speakers: I'm looking at Klipsch 5.1, Monsoon MM2000, and Logitech Z-680 ... I'm not really a gamer, but DVDs and music are my interests ... are these speaker systems "Mac friendly"? and would I need special sound cards? and how do they hook up to the Mac (my current speakers are USB attached)?