Witcher 3 Physx GPU

[JigMcGalliger]

I just checked using NVidia control panel's visual indicator. Even with 660Ti dedicated to Physx, the game is running Physx off the CPU. Anyone know how to fix this glaring problem?

CDPR said it would support GPU Phsyx from the start:
http://physxinfo.com/news/11558/the-witcher-3-will-support-gpu-physx-now-officially/

 

[JigMcGalliger]

well if anything else the core of PhysX rely on CPU (mostly). only few simulation that is can be very taxing to CPU were made to run on GPU. but today CPU is quite capable and nvidia have improve CPU PhysX a lot (especially with PhysX version 3.x.x). probably why developer like Bohemia Interactive willing to delay ARMA 3 in favor of nvidia finishing PhysX 3 and CDPR themselves replace havok (Red Engine 2) with PhysX 3 (Red Engine 3). even Project Cars only using CPU based PhysX in their game.

The issue here is Physx 3.x can still run GPU phsyx, it is meant to allow the CPU to be a viable option for competing hardware... that and Nvidia want to license physx as a full middleware, not just a graphical addon (as it is with W3). This is the first instance of the nvidia and a developer locking nvidia users out of nvidia's own proprietary features that they sell so heavily. That is a big problem and I doubt this won't be the first instance.

 

[renz496]

So what the problem with gpu physx? And what did you mean nvidia locking their user from nvidia own tech?

 

[Eggz]

I just don't understand why they would lock it to the CPU. Even the fastest CPUs can't handle PhysX properly. I ran it on a 4930k at 4.5 Ghz, and no CPU will run the game significantly faster than that. If you run a PhysX benchmark or game with GPU acceleration - once on CPU and once on GPU - you'll see a huge difference. My test were more than double performance, which was the difference between beautifully smooth and totally unplayable. If anyone knows this, it's Nvidia and game developers. I wonder what gives.

 

[renz496]

I just don't understand why they would lock it to the CPU. Even the fastest CPUs can't handle PhysX properly. I ran it on a 4930k at 4.5 Ghz, and no CPU will run the game significantly faster than that. If you run a PhysX benchmark or game with GPU acceleration - once on CPU and once on GPU - you'll see a huge difference. My test were more than double performance, which was the difference between beautifully smooth and totally unplayable. If anyone knows this, it's Nvidia and game developers. I wonder what gives.

that one you got to ask CDPR. but make no mistake. nvidia has improve PhysX a lot under PhysX 3. that's including multi threaded support. and i dare to bet some dev were interested with PhysX because of that. right now Havok are making noise about what game use their solution. they never bother to do it before.

 

[17seconds]

The PhysX effects in the Witcher 3 are really CPU quality effects from what I have seen. They are nowhere near the level of GPU effects that you'll find in Batman Arkham or Borderlands. These games feature cloth, fluids, and objects that react individually to the environment. I don't yet own the Witcher 3, but all I have seen in that game is mainly smoke/dust effects during a weapon strike. Can anyone confirm any other effects in that game?

 

[Eggz]

That and the hair stuff. . . . It's really not worth turning on given the CPU implementation, though.

Since Steam does free and easy returns now, you can just buy and return if you don't like it - like I did.

 

[17seconds]

I wasn't including Hairworks since I don't think that's a true PhysX effect. My understanding is that Hairworks is its own thing and makes use of the GPU to render tesselation and physics effects. Not sure if its a CUDA PhysX thing though.

 

[Eggz]

I ran through a lot of areas that included cloth, liquid, hair, etc., and nothing triggered any activity whatsoever on my PhysX card. In all PhysX games and applications with GPU-rendered PhysX effects, the dedicated PhysX card at least does something more than 0%, but it just didn't happen in the Witcher 3.

Plus, if you look at PhysX Info's website, it even says the effects aren't GPU accelerated. I checked after seeing no utilization of my PhysX card, which was a bummer because they originally announced that GPU PhysX was going to be supported - http://physxinfo.com/news/11558/the-witcher-3-will-support-gpu-physx-now-officially/ - but then they pulled it.

Here is the official word, though: http://physxinfo.com/index.php?p=gam&f=fx

If you look, there's a "?" rather than a check mark, which would have indicated GPU PhysX. Putting that together with online reports and my own tests showing 0% utilization of my dedicated PhysX card, there's little room for doubt.

There's no hardware accelerated PhysX in the game :-/

 

[17seconds]

I ran through a lot of areas that included cloth, liquid, hair, etc., and nothing triggered any activity whatsoever on my PhysX card. In all PhysX games and applications with GPU-rendered PhysX effects, the dedicated PhysX card at least does something more than 0%, but it just didn't happen in the Witcher 3.

Plus, if you look at PhysX Info's website, it even says the effects aren't GPU accelerated. I checked after seeing no utilization of my PhysX card, which was a bummer because they originally announced that GPU PhysX was going to be supported - http://physxinfo.com/news/11558/the-witcher-3-will-support-gpu-physx-now-officially/ - but then they pulled it.

Here is the official word, though: http://physxinfo.com/index.php?p=gam&f=fx

If you look, there's a "?" rather than a check mark, which would have indicated GPU PhysX. Putting that together with online reports and my own tests showing 0% utilization of my dedicated PhysX card, there's little room for doubt.

There's no hardware accelerated PhysX in the game :-/

Yeah, I saw that on Physxinfo. During the first couple of weeks after the release of Witcher 3, they indicated that it had full GPU effects. After that, they figured it out and put a ? in that column. It's pretty clear that CDPR doesn't want this to be widely clear and advertised after making contrary claims during its E3 presentation.
http://physxinfo.com/news/11558/the-witcher-3-will-support-gpu-physx-now-officially/

 

[renz496]

Personally I'm still going to get witcher 3 but not now.

 

[17seconds]

Personally I'm still going to get witcher 3 but not now.

I like to wait until all the DLC are released and then get the whole bundle for one low price on Steam.

 

[renz496]

Personally i'd prefer to get it from GoG instead of Steam.

 

[Eggz]

Looks like someone claims to have figured out a text hack to use GPU for PhysX in Witcher 3 - finally!

However, if you still want to run PhysX on the GPU, navigate to your "...Documents/The Witcher 3" folder and make sure the following line is tweaked as follows in your "user.settings" file (use a text editor such as Notepad to open it):

[Visuals]
AllowClothSimulationOnGpu=true (default value: false)

http://forums.cdprojektred.com/threads/55988-After-Update-1-08-and-Driver-355-60-for-win-10-no-Physx-Gpu-in-ihe-game-just-physx-Cpu