TrustedReviews have looked at the Asus Xonar D2 Sound Card

If you're after a solution that offers a high quality home theatre experience or want something for entry-level music production, the Xonar offers a strong package. With a comprehensive PDF manual (marred by the usual translation mistakes), Vista drivers and a thoughtful design, this is an impressive and capable card.

Asus Xonar D2 Sound Card Review