Xbox Audio

Hi guys,
I'm trying to get my Xbox360 hooked up properly to run on my Monitor/Speakers. Got the monitor part done. I'm running a Radeon x1900XT and it has no composite-in. Just Video-In, Video-Out, Svideo-In, Svideo-Out, and HDTV out.

I'm looking for a way to get the audio from my Xbox composite cables, to my computer speakers. Any sugestions?

connect the audio out of the xbox 360 to the audio in of your soundcard or motherboard using approriate digital coaxial or spdif, or analog rca or minijack adapters and cables.