I've bought some demo software to trial for a company and they say i need the most up-to-date drivers that are available.
What they dont say untill you moan at them for days on end because it doesnt work, is that DirectX needs to be 7 - 8.1 . and tbh this is just for the install program!
Believe it or not... this company im trialing for is not MS.
I heard here a while back that there was a program that could roll back your dx versions. I've got 9b. I want 8.1 and running XP.