ok u will need to get some connectors. These are kind of what your looking for , just a few more connectors seeing as u most likely have a 5.1+ sound card You should have an AUX on your stereo , once you have the pc plugged into the AUX plugs on theback of the stereo u just switch to AUX mode then all sound will go through your stereo speakers, Hopefully you have enough speaker connectors on it so you can plug in individual speakers, eg 1 for left 1 for right 1 for sub 2 for surround etc etc. Its kind of hard to explain, if i get time ill knock up a quick image of what i mean in photoshop.