I'm currently running a simple Linux box (geexbox) to output media (TV, movies, music, etc.) to my Olevia 37 in. LCD monitor.

My sound card is a simple Turtle Beach Riviera that supports RCA composite and S/PDIF output.

At the moment I am just connecting via RCA to my TV.

I am ready to upgrade to a better sound system, but I don't have any clue where to begin.

I'm thinking I'll start with the receiver and set of speakers. I live in a small, one-bedroom, flat and I don't want to drive the neighbors nutz.

So...where to start? I've got a 500$ budget.