Well, in most cases I would say not to go out and buy a card since onboard has improved so much. However, since you already have a (very nice) card laying around, why not? It can't hurt and should make your audio even better (although the improvement may be lost by the speakers).
man i have an X FI PCI card and it sounds 10 times better then realtek and FYI creative fixed the windows 7 issue a cple months ago MagicPants has no clue what he is talking about if your worried about latancy issues there is a program that you can use to adjust that but i never experienced any problems. USE THAT X-FI MAN YOU will be much happier with sound quality versus that crappy onboard sound especially if its realtek or via crap, ADI is the only half decent onboard and even that cant compare to an X-FI
I doubt there is a program that will fix the "latency" issues that pants was talking about. I could see a program that will fix the problem you seem to be thinking of. I've heard of the issues that CL has had with vista, I'm assuming they exist with Win7. I haven't heard of it being properly fixed and welcome a link showing that they have been.
Well I think I am experiencing that issue (stuttering) while playing COD MW2 on Win 7..don't know if it's the game or the card though (I also have an X-Fi Extreme Gamer)...haven't tried other games yet.
As a followup, I have installed the card and the difference in sound is off the charts! I originally purchased the card to go into my old P4 that had the RealTec on-board chip-set.
With this board having such a robust on-board audio setup, I had assumed that the gain would have been too little to bother. I was wrong!
Also, I had read quite a bit about problems existing with Creative Labs and Win 7 64 bit with regard to drivers, etc. They have an update on their site, and everything installed perfectly with no problems.