PC1 PhysX always on CPU

[dsuspense]

I tried assigning PhysX to SLI 1 and SLI 2 cards, but the PhysX indicator always shows CPU.
I am wondering if that is causing my poor FPS.
I can only get about 45-60 FPS will low settings, with both single and SLI setup for a nVidia GeForce GT 650M setup...

 

[yusupov]

that doesnt sound bad for gt650M although it sounds like SLI isnt working properly if youre getting the same results.

physx will always be CPU-only. the games in which its GPU-based are when its used for graphical effect which isnt the case here. i have a dedicated physx card so if nvidia thought it had a meaningful impact on performance im sure theyd give it to the gpu which is just sitting there doing nothing.