A disclaimer first: The following post is my personal opinion and by no means an official recommendation. And with that out of the way I'd like to share a little problem I was facing last month. I was looking for a sound card with 192 kHz/24 bit playback and Vista x64 support in form of a low profile PCI card. It wasn't easy but I found one: The Audiotrak Prodigy HD2. I've been using this card for about two weeks now with a 64-bit Vista machine and 4 GB RAM and I'm pretty happy with it so far. Just to set the right expectations, the card does not have a couple of features you find in other sound cards like a high performance DSP or multichannel output. But for people like myself who are primarily interested in the playback of HD stereo sources it is definitely an interesting option especially since it provides both a quite powerful headphone out as well as RCA line out.
This posting is provided "AS IS" with no warranties, and confers no rights.