I just installed Vista Ultimate on a Inspiron 6000 . The only device that Vista did not automatically set-up for me was the Audio.
I run the set-up for the original XP driver (R99254) ...for that Audio device ....and viola ....I got sound working perfectly on Vista using the XP driver.
A check of the device manager shows that ALL divices are installed and working correctly ....and my tests have confirmed that.
In other words ...there are no special drivers you need ...Just the Vista install ...and the original XP audio driver...( Which is R99254 ...and which can be easily downloaded if you don't have it.