How can I switch PhysX work to CPU if my GPU is AMD...

Solution
If a game that supports PhysX is installed, the separate PhysX application that is required for (software) PhysX effects would have been automatically installed along with the game. The PhysX operation then automatically runs on your CPU.

Hardware accelerated PhysX is another story altogether... For hardware accelerated PhysX to work at all, an Nvidia graphics card has to be installed. There is no way around it.
If a game that supports PhysX is installed, the separate PhysX application that is required for (software) PhysX effects would have been automatically installed along with the game. The PhysX operation then automatically runs on your CPU.

Hardware accelerated PhysX is another story altogether... For hardware accelerated PhysX to work at all, an Nvidia graphics card has to be installed. There is no way around it.
 
Solution


I thank that was being processed for AMD CUs because high PhysX setting drops FPS while my CPU is a i7 4790...

Thank you for the info and sorry for my bad english.
 
i never test this myself (since i don't have the hardware for it) but from my understanding GPU PhysX will only appear when you have nvidia gpu (or you don't mix in nvidia/AMD discrete gpu in one system). if you don't have nvidia gpu the calculation will not be offload to cpu but instead it will disabled entirely. so what you have is the basic physics effect. the effect that will be calculated by CPU regardless you have nvidia gpu or not.
 


i think so far Borderlands 2 were the only exception that gpu PhysX can work even with AMD gpu being used. but it run on CPU by default. so if you set PhysX to high of course the performance will be affected. just use the lowest setting for PhysX if you have AMD gpu.