I'm thinking about getting myself a sound card ( or amp, or both), my question is will I notice an improvement in audio quality over the on board sound in my cheap Asus motherboard? I listen to music with my hd 25ii and mdr v6 headphones and generally use flac or 320 mp3 files. Any advice...

Sweet thanks, one more thing, how do I know if my classic is compatible with rockbox? There are a bunch of different versions, mines an 80gb but I'm not sure on the specifics.  

I'm thinking about installing rockbox on my classic but would someone mind finding out if rockbox has the feature I think all ipods have where the headphones are pulled from the jack and the music pauses? My classic is faulty in that it'll pause all the time even when the headphones are in...