Hey, I did this just last weekend. Upgraded from a SB live to Audigy -2. Don't know why, maybe I'm an idiot, but nothing I could do would get the darn new card to work. I unisntalled the old SB drivers and old Creative software first, then installed the card and went through the software intall of driver and programs. My computer would not recognize the card. After much fiddling and such I just re-formatted the darn c drive. Card works beautifully now.
Probably not what you wanted to hear though. I'm sure I messed up somewhere, but I have no idea where. I do hope your experience goes better than mine.
One final point though. I do really, really like the improvement in sound quality. It's a big improvement...woof!