I have an AMD card... The CCC does not have such an option.

Can somebody explain to me, who has no clue about how software and hardware communicate with each other, what PhysX is exactly and what it will do in the game?
I have a gtx 750Ti OC and an i7 2600k with 3,4 ghz.
I can run the game on pretty high settings but i have nothing besides anti aliasing enabled on the post processing section so far.
I started out with the recommended "all low" and then turned it up bit by bit, never noticing any loss in fps.

My physx is currently set to "auto", so shouldn't it automatically pick the CPU if the GPU is too busy?

AMD card don't have the specific hardware that physx use and thus your cpu is used instead.
Up to the game maker how much physx you get in the game and then again what share of it ati users get trough their cpu instead.

@AiCola , I don't know that much about it but I would guess that it only use your gpu, unless you specify otherwise.


Personally I think physx isn't much more than a cheap ploy by nvidia to steal more of the market.
Amd does the same but so far they don't have enough money/marketshare to convince most game makers to use their toys instead.
So just ignore the fluff and buy whatever card gives you the best performance/money at the time. :)

Let me try this later, just for record, I'm having 50-64 fps with occasasion dips to high 40s fps, nothing too distressing.

Let's see if using the CPU for physx will have an improvement.

Thanks for the suggestion.

I just set it to CPU and i tested it for a short time and it felt like the framrate actually got worse.

Theres 2 types of physx. The hardware accelerated one which only works on nvidia cards and the software only one which works on anything and uses the CPU (and is much slower).

W3 is the lesser, software based one which will only run off the CPU :/

For what it's worth, I tested this out last night because I also have a 670 GTX but a slower CPU, an i5-2500K. I've been having trouble attaining a stable 30fps because I won't turn off hairworks or turn down all the settings that I should.

Using nvidia's shadowplay feature to display the framerate, I definitely got a 5-8fps increase when I switched PhysX over to the CPU. Depending on what's on screen, I still take big hits to framerate with my settings, but I'm now locked at 30fps for most of my regular gameplay.

Thank you very much for the tip.