Everyone here who posts about how internal sound cards are crap obviously never looked at the result of RMAA tests. I've done numerous tests of varied motherboard/internal/external(pro) audio hardware and I can assure you that Asus Xonars easily beat the crap out of a number of external pro audio interfaces. And contrary to your ears, these tests never lie. Also, I'm speaking about the cheapest Xonar (Xonar DS) here. Just because Asus puts a load of useless gadgets into its cards (DolbyTrueSurroundMegaBassExploder and the like) doesn't mean that it doesn't put high quality components in them, too. Components which are described in detail on the Asus website (including complete references for the DACs and OPAMPs). As for the noise: as surprising as it may sound, my tests show that interference from other components inside the PCs usually do not happen inside the case but immediately outside, into the audio cable (where the audio card cannot protect the signal). This means that the quality of the audio cables directly connected to the sound card if quite important, and I've seen surprising differences in noise floor between cheap RCA cables and more pricey ones.