Re: Need help choosing a sound card.
Just get something X-Fi. It has a great mechanism that detects patterns in sound and guesses the missing data from compression... and does a great job in it. Also, X-Fi has drivers for ALchemy/OpenAL, which is a technique that bypasses the absence of DirectSound in DirectX 10, allowing you to use your sound-cards functionality if you have Vista.
I have the first PCi-Express Sound card, which is BRILLIANT and an X-Fi. I'd recommend that. It's about 100 AU dollars.