RTX 50 Series silently removed 32-bit PhysX support.

[The Plague]

I found this on Reddit.

I made a thread on the Nvidia forums since I noticed that in GPU-Z, as well as a few games I tried, PhysX doesn't turn on, or turning it on forces it to run on the CPU, regardless of what you have selected in the Nvidia Control Panel.

Turns out that this may be deliberate, as a member on the Nvidia forums linked a page on the Nvidia Support site stating that 32-bit CUDA doesn't work anymore, which 32-bit PhysX games rely on. So, just to test and confirm this, I booted up a 64-bit PhysX application, Batman Arkham Knight, and PhysX does indeed work there.

So, basically, Nvidia silently removed support for a huge amount of PhysX games, a tech a lot of people just assume will be available on Nvidia, without letting the public know.

Edit: Confirmed to be because of the 32-bit CUDA deprecation by an Nvidia employee.

C'mon, Nvidia...

 

[ShrimpBrime]

Cause windows 11 only comes as 64 bit.

And nobody cared about Physx. Why start now?

 

[Onasi]

I mean, I guess I understand the decision from the engineering standpoint to remove bloat and PhysX is dead in the water nowadays anyway, but this is hilariously scummy. Especially the fact that they haven’t told anyone outright. It would have been like if Intel didn’t inform everyone ahead of time that Arc is DX12/Vulcan centered and older APIs aren’t supported in-hardware, but use an emulation layer. Except here there is just straight up no support without any fallbacks. Although not as debilitating I guess since PhysX supporting games weren’t THAT common, let alone those where it was implemented in a meaningful way. In any case - I wouldn’t mind if they just actually explained it in advance.

 

[R-T-B]

Cause windows 11 only comes as 64 bit.

And nobody cared about Physx. Why start now?

32-bit games still work.

Also, CPU side physx is arguably one of the most used APIs for physics in town (yes even today courtesy Unity). GPU-side is pretty dead though, yeah.

 

[Dr. Dro]

Not PhysX specific, Nvidia removed legacy 32-bit CUDA binary support from RTX 50 series. If this is important, stick to RTX 40 and below

NVIDIA Support

nvidia.custhelp.com

 

[ShrimpBrime]

32-bit games still work.

Also, CPU side physx is arguably one of the most used APIs for physics in town (yes even today courtesy Unity). GPU-side is pretty dead though, yeah.

CPU side, small set number of particles.(software*Unity)
GPU side, 10 thousand particles+.(hardware)

 

[R-T-B]

CPU side, small set number of particles.(software*Unity)
GPU side, 10 thousand particles+.(hardware)

Yes but none of that matters if its exclusive to your brand and as such, almost literally no one uses it.

 

[ShrimpBrime]

Yes but none of that matters if its exclusive to your brand and as such, almost literally no one uses it.

Exactly.

So why all of a sudden should any one care about 32 bit physx, let alone 64 bit?

(I was once a big advocate for physx when Ageia had released it 20 years ago.)

 

[Dr. Dro]

Exactly.

So why all of a sudden should any one care about 32 bit physx, let alone 64 bit?

(I was once a big advocate for physx when Ageia had released it 20 years ago.)

I suppose past a point, backwards compatibility can become a burden. Nvidia has supported and maintained software going back to the Windows XP days - eventually you need to drop the baggage.

That's why Microsoft has been changing Windows 11 and pushing up system requirements ever higher, for example, they just removed the Intel 8th, 9th and 10th Gen CPUs from the list of supported processors for 24H2 and banned their use in OEM systems a couple of days ago.

I'm not sure how many applications still target a 32-bit CUDA runtime, considered 32-bit Windows support has been dropped back in March 2018, almost 7 years ago alongside the Fermi architecture GPUs. The 391.35 driver was the last to support this configuration. My best guess is that at this point in time, most of the programs and compilers were already upgraded and replaced, just leaving older games behind.

 

[ShrimpBrime]

I suppose past a point, backwards compatibility can become a burden. Nvidia has supported and maintained software going back to the Windows XP days - eventually you need to drop the baggage.

That's why Microsoft has been changing Windows 11 and pushing up system requirements ever higher, for example, they just removed the Intel 8th, 9th and 10th Gen CPUs from the list of supported processors for 24H2 and banned their use in OEM systems a couple of days ago.

I'm not sure how many applications still target a 32-bit CUDA runtime, considered 32-bit Windows support has been dropped back in March 2018, almost 7 years ago alongside the Fermi architecture GPUs. The 391.35 driver was the last to support this configuration. My best guess is that at this point in time, most of the programs and compilers were already upgraded and replaced, just leaving older games behind.

It kind of went both ways. Trying to Install Windows 7 on Z390 is a pain in the butt, and nearly impossible on today's hardware.

Par for the course I suppose.

 

[DemonicRyzen666]

32-bit games still work.

Also, CPU side physx is arguably one of the most used APIs for physics in town (yes even today courtesy Unity). GPU-side is pretty dead though, yeah.

CPU PHYSX IS SLOW A.F ESPEICALLY ON DX12! the CPU is already doing too much on dx12 to haveto do physX too. Any game that runs cpu physX all have stuttering problems because of it.

 

[Carlyle2020hs]

I´ve had 2x GTX 580 in sli and a dedicated GTX 460 with 1Gb ram for PhysX

Just to play the witcher 2 on full tilt back in 2011.

The Witcher 3 in 2015 did already account for AMD cards, so it had modes to run with and without Physx.

I hope there are more games like that out there than we think.

 

[ir_cow]

Hardware Physx has been janky from the start. No loss in removing it.

 

[ShrimpBrime]

CPU PHYSX IS SLOW A.F ESPEICALLY ON DX12! the CPU is already doing too much on dx12 to haveto do physX too. Any game that runs cpu physX all have stuttering problems because of it.

I uh, well see there, maybe some....

Unity PHYSICS runs on the cpu in the game engine taking at least 1 core.

Nvidia PHYSX runs on the gpu or on a second GPU as @Carlyle2020hs has just mentioned.

Physx can not be run on a CPU. It must be run on a dedicated Physx Processing Unit (this is not a gpu or cpu) or on the NVidia Graphics Processing Unit.

(Maybe you know all this, but for readers that may not understand)

But you are correct, some games where not optimized well for physx. Can't release a game if you spend an additional year on physx implimentation.

 

[TheDeeGee]

Cause windows 11 only comes as 64 bit.

And nobody cared about Physx. Why start now?

PhysX is still used in titles released as recent as 2024.

It's not even remotely dead.

 

[ShrimpBrime]

PhysX is still used in titles released as recent as 2024.

Not since NVidia Physx went open source. (2018)

 

[R-T-B]

CPU PHYSX IS SLOW A.F ESPEICALLY ON DX12! the CPU is already doing too much on dx12 to haveto do physX too. Any game that runs cpu physX all have stuttering problems because of it.

YES. I'M WELL AWARE. WHY ARE WE YELLING?

Hardware Physx has been janky from the start. No loss in removing it.

Yes, but I can't deny a vendor agnostic gpu accelerated physics engine that worked well could be very very useful.

But PhysX isn't that.

Not since NVidia Physx went open source. (2018)

That's precisely why its still used. Keep in mind only the CPU version is open source.

 

[Dr. Dro]

It kind of went both ways. Trying to Install Windows 7 on Z390 is a pain in the butt, and nearly impossible on today's hardware.

Par for the course I suppose.

At that time I had AMD, I tried to get Windows 8.1 installed back when I had my 5950X, I was actually mostly successful but deadstopped by the lack of any Windows 8.1 drivers for the RTX 3090. It took over a year after that for some smart folks to make up some fake root certificates and modify the drivers so they could load Ampere cards, nowadays 3090's about the fastest hardware that can run on that config. Windows 7 would be just madness.

 

[R-T-B]

Physx can not be run on a CPU.

Yes it can. There is a whole seperate (more used) version for this. Its the one nvidia open sourced.

I know this because I work with it regularly in my KSP mod. Not gonna lie, its kind of awful.

 

[TheDeeGee]

Not since NVidia Physx went open source. (2018)

Already 6 titles that are planned for 2025 use it.

List of games that support Nvidia PhysX - PCGamingWiki PCGW - bugs, fixes, crashes, mods, guides and improvements for every PC game

www.pcgamingwiki.com

 

[LabRat 891]

Cause windows 11 only comes as 64 bit.

Makes sense to me.

And nobody cared about Physx. Why start now?

AFAIK, PhysX (Today) exists as an API or 'extension' for CPU (vendor agnostic) *and* CUDA-based (nV propietary) physics.
I've seen it as a requirement for games, even running all AMD.

Aegia PhysX and most nV-propietary CUDA implementations of PhysX are *long* depreciated.
Kinda like 3DFX SLI vs. nV SLI, nV bought the company and IP, later re-using same/similar branding/naming for a similar product.

 

[ShrimpBrime]

Already 6 titles that are planned for 2025 use it.

List of games that support Nvidia PhysX - PCGamingWiki PCGW - bugs, fixes, crashes, mods, guides and improvements for every PC game

www.pcgamingwiki.com

That wiki is fked up.

The dates listed are the dates they updated the list. (I THINK).

Last Airbender came out in like 2005, and that wiki says 2023.

Please double check all of those games and get back to me on this. (Because there are no recent games that specifically advertise NV physx open source or not, that I am aware of.)

Makes sense to me.

AFAIK, PhysX (Today) exists as an API or 'extension' for CPU (vendor agnostic) *and* CUDA-based (nV propietary) physics.
I've seen it as a requirement for games, even running all AMD.

Aegia PhysX and most nV-propietary CUDA implementations of PhysX are *long* depreciated.
Kinda like 3DFX SLI vs. nV SLI, nV bought the company and IP, later re-using same/similar branding/naming for a similar product.

Ah yes, thank you for this.

 

[bug]

I mean, I guess I understand the decision from the engineering standpoint to remove bloat and PhysX is dead in the water nowadays anyway, but this is hilariously scummy. Especially the fact that they haven’t told anyone outright. It would have been like if Intel didn’t inform everyone ahead of time that Arc is DX12/Vulcan centered and older APIs aren’t supported in-hardware, but use an emulation layer. Except here there is just straight up no support without any fallbacks. Although not as debilitating I guess since PhysX supporting games weren’t THAT common, let alone those where it was implemented in a meaningful way. In any case - I wouldn’t mind if they just actually explained it in advance.

This is mainly a change in CUDA. No more Win10 support, no more 32bit support either. Both CUDA and PhysX probably work just fine if you stick to prior CUDA versions.

Fwiw, this is how Nvidia has always kept their software stack clean(ish): they deprecate unused features, declare older architectures feature complete and then they move old these onto a legacy branch. There, it will still see security and bug fixes. Only they no longer pollute the mainline.

 

[DemonicRyzen666]

Not since NVidia Physx went open source. (2018)

No they didn't. The only part that open source & I wouldn't even call it open source if you actually read it. is the cpu physX. It's technically not mod-able for games engines either, because Nvidia can sue you for modding it.
They still only allow CUDA for GPU accelerated physX please stop lying along with Nivida.
Nvidia doesn't "open source" anything because it they did both cuda core designs & a cuda core translation layer would exist.
They already went to sue the ROCm developer for his translation layer.

 

[ShrimpBrime]

No they didn't. The only part that open source & I wouldn't even call it open source if you actually read it. is the cpu physX. It's technically not mod-able for games engines either, because Nvidia can sue you for modding it.
They still only allow CUDA for GPU accelerated physX please stop lying along with Nivida.
Nvidia doesn't "open source" anything because it they did both cuda core designs & a cuda core translation layer would exist.
They already went to sue the ROCm developer for his translation layer.

Yes they did. SDK Physx 5.0 is all open source. It's exactly what is used in game engines. Pixar films, all right here in the link.

I don't know too much about legality of open source software, I shall admit.

Open Source Simulation Expands with NVIDIA PhysX 5 Release | NVIDIA Technical Blog

Learn about the latest version of the NVIDIA PhysX SDK, the primary physics engine of NVIDIA Omniverse.

developer.nvidia.com

But, I'm no developer, play around with the demos from time to time though.