Try out the onboard audio in a recent motherboard, you might be surprised by what you hear.
Creative Sound Blaster Zx
http://www.tigerdirect.com/applicati...?EdpNo=7769071
I've tried that with the Biostar TA-970 that I have in my desktop. It was crackle-galore in high and low frequency response. On a silent-cd test the onboard was noisy. I had to install a sound card. I recommend an sb0770 or sb0880. 24-bit/192k sounds amazing compared to onboard. If you're using analog 2.1 or better speakers, definitely consider the two cards listed. Creative has been updating their drivers and I don't have a single issue with these cards.
Isn't the biggest difference between on-board and something like the Audigy ZX is the ability to output (decode?) DTS and DD? (Or at least their HD version like DTS-HD)
Xonar DX, works great with any setup up to 7.1, especially headphones (thanks to Dolby Headphone). Creative's drivers take sth like 10x more space. If you have particularly high impedance headphones, consider Xonar DGX with built in headphone amp.
It still doesn't cost the OP anything (other than time) to try the onboard. Not every implementation is bad as a low-end Biostar from several years ago.
Unfortunately the Onboard sounds terrible, definately worth the try though....ordered a Xonar DX, thanks all