Hi,
With the takeover of Ageia by nVidia, nVidia seems to have decided to drop support for Ageia PPUs. There does not seem to be any windows 7 support for my BFG Tech Ageia PhysX card on the nVidia websites (BFG Tech site no longer exists - they stopped selling GPUs), but on some other forums I have read that you can somehow work with previous drivers.
I tried uninstalling all drivers and then installing the  PhysX_8.09.04_SystemSoftware driver package, which, according to these other  forums, should make windows recognize the Physics PPU. However, that did  not work. I even tried installing the really old drivers that came with  the card on a CD. The card is definitely plugged in correctly and  connected to the power supply unit. 
The card worked fine on Vista. I payed 200 dollars for it and would be pretty annoyed if it turned out its useless now. Do you guys know how to solve my problem?
Cheers,
Duke