Windows 7 - physX with an AMD gpu ?

I used to have an SLI set-up w/ 2 Asus GTS-250 Dark knights 1 gig ddr3 each and recently upgraded to a (1.) Radeon HD 6950 2 gig ddr5. I noticed in my 'change or remove programs' that nVidea physX is still installed. Do I need it and will removing it effect my PC in a negative way ? A simplistic reply would be greatly appreciated, thank you...

Depends on what games you have installed as to whether you need it or not. Some Physx enabled games won't work regardless of whether you have an AMD or Nvidia card if it isn't there (Crazy Machines 2 for example). The game doesn't have to support GPU accelerated Physx (which you won't get with an AMD card), but those that use the software version will still need it.

Here is the list of all Physx games on the PC,

PhysXInfo.com - Projects using PhysX SDK

the ones with a green check mark are the few (23 so far) that can use GPU accelerated Physx.

So to answer your question, you can uninstall it if you don't have any of those games, otherwise I wold leave it.

Thank you very much for your quick and to the point answer to my 'Q.' I play some games that require physX so I'm just going to leave it as is, my machine is running fine, I just wanted to know if it was still a necessary program even though I switched to an AMD gpu. Yor knowledge is greatly appreciated !

Correct me if I'm wrong but I think PhysX will only work on NVIDIA hardware.

You can check this by using GPUz.

To enable PhysX on ATI cards, you need:

1. a dedicated PhysX NVIDIA card (ie, you add an NVIDIA card to your setup),
2. you need modded drivers to enable PhysX.

How To: Run PhysX in Windows 7 with ATi Cards - Overclock.net - Overclocking.net

IMO, PhysX makes a difference, however there are too few titles that utilize this feature. Unless you are into benchmarking or getting the that extra x% in performance, I don't see a need.

Also, you can leave it installed on your system.

OK you're wrong. You really think that a game developer/publisher would put out a game that only worked with on GPU manufacturer's cards? They would cut out a rather large portion of any potential customers if they tried pulling something like that.

You're thinking of GPU accelerated Physx, in which case you are right that it only works on Nvidia hardware. Where you're wrong is the software rendering of Physx which is how it works in every game that uses it, and only uses the GPU in a few (a whole 23 games to date either out or still being made) games. There are far more games that use software based Physx than GPU accelerated (291 according to the link I posted previously). It is also used in games on the PS3 and Xbox 360.

Thank you both for taking the time