I needed a low profile PCI sound card with optical output so my choices were pretty limited.
I ended up with a ASUS Xonar DS and I've been very pleased with it. It does what it's supposed to. I've A/B compared the original CD playback to the FLAC playback and I can hear no difference whatsoever.
I recently discovered that I needed to go analog out from my HTPC in order for "zone-2" to play. The analog output of the card wasn't as good as I had hoped BUT changing out the op-amp (it's socketed) made for a real improvement on the analog side. A fairly cheap upgrade too. A little over $5 for the new op-amp.
Is it the end all be all of sound cards? Of course not. But for under $50 it's pretty good and a world better than whatever crap was built in to the mobo.
Edit to add:
I have an unused SoundBLASTER Audigy SB1394 PCI card here that's not being used. It's a model: SB0090. I'd be happy to send it to you for the cost of shipping if you want to give it a try. You'll need to track down the drivers for it. As I recall it was one of the nicer sound cards out there.
I read Playboy magazine for the same reasons I read National Geographic magazine.
I like to see pictures of places I know I´ll never visit.
The new "slimmer trimmer" system is listed in my System Profile section. Check it out.