Which sound quality is better iPod or PC with realtek HD sound card?

I am a big trance listener I have lots of trance songs probably 200 GB. The sound quality is very important for me I use winamp with ozone it sounds good. But my sound card is too old for these songs and I want to buy new PC with a good sound card or iPod Nano. I'm a little bit confused about sound cards. So I need you advice about this?