The ALC codecs are getting driver updates at least, I read an artical here (I believe) that Audigy's last driver update was Last November and its not fully compatable with nforce4 yet (only the most popular AMD platform atm).
About win xp, u need to load at least 3 times for it to be put in the prefetch directory, and also try running bootvis (from microsoft) to optimise the boot-time of ur system.
Im interested to see how this works in BF2, since previous drivers would place sounds across the map as right beside u. America's Army was always fine. I chose to run these drivers after I isolated a slight freeze, pausing down to the Nvidia implimentation of sound drivers. Im alot happier without this freezing. Had to kill ATItool also since this game mega lags for no apparent reason. :beer: