Check the front page of anandtech for the dailytech article on creative. then throw your audigy in a firepit and use your onboard 😀.
Honestly, I would just use the onboard card. I've got an audigy 2 sitting in my closet, havent used it in ages. Sure, some of the eax stuff is nice, but honestly, you wont notice it much.
EDIT: forgot to mention about some of the crash issues related to the awful driver implementation by creative under vista. onboard (or a sound card by someone else) just seems like a better, less hassle free bet right now.