[dgbiker1]

How the subs work depends on how you set it up. For music, I just set it up like a normal 2.1, but connect a y-splitter from the line/headphone out on the soundcard. That way the front & rear get the same signal. If you want true 4-channel sound just plug the front & rear into the respective sound card inputs. The rear channel still gets the broadband signal with bass, and the crossover network in the sub will take care of separating bass from everything else. In that case you just have surround bass.

Another option (what I'm doing now) is to get the Promedia 2.0 speakers for the surround as they're a good bit cheaper. They sound better than the 2.1 satellites and you don't have to worry about the extra sub. You won't get the extra bass, but I'd recommend going with a separate sub anyway as it will get you down to lower frequencies than the 2.1 subs do.

As for the speakers, you probably can't power a huge set of speakers with it, but I think the amp is good for about 40W IIRC. That's plenty to drive decent bookshelf speakers at a good volume. I'm using Polk RS1s (I think) and they sound fantastic through that setup.