Why PhysX Suddenly Matters Again
PhysX is one of those old school PC gaming technologies many of us assumed was gone for good. It first showed up when dedicated physics cards were a thing and has quietly faded into the background over the years. But with Nvidia’s new RTX 50 series graphics cards, PhysX has unexpectedly become relevant again.
The drama started when Nvidia dropped native support for 32 bit CUDA applications on the RTX 50 series. That meant older games using 32 bit PhysX could no longer run their physics effects on the GPU in the usual way. Instead, all those calculations would fall back to the CPU.
For these classic PhysX heavy titles, that is a real problem. Hardware accelerated PhysX was designed to shift demanding in game physics from the CPU to a dedicated processor, originally on separate PhysX cards and later on Nvidia GPUs. This freed up CPU resources and allowed developers to go wild with smoke, cloth, particles and debris. Turn PhysX on without GPU acceleration and your CPU gets hammered. Turn PhysX off and a lot of those cool effects simply vanish.
Nvidia has since walked things back a bit by adding selective per game PhysX support for RTX 50 series cards via new drivers. That is where the new round of testing comes in, focused on two of the best known PhysX showcases on PC: Batman Arkham Asylum and Batman Arkham City.
Batman Arkham Asylum and the Cost of PhysX
The test system is a modern high end gaming PC built around an AMD Ryzen 7 9800X3D, 32 GB of fast DDR5 and RTX 50 and 40 series graphics cards swapped in and out for comparison. Frame caps were removed via config files to show the real performance ceiling.
In Batman Arkham Asylum, PhysX is not yet officially supported in the new RTX 50 series driver stack. That makes it a great example of what happens when 32 bit PhysX effects run without proper acceleration.
With an RTX 5080 and PhysX set to High, the game averages just 50 frames per second with 1 percent lows at 31 fps. Turn PhysX off and performance rockets up to 274 fps on average with 179 fps 1 percent lows. That is an enormous drop of over 80 percent when PhysX is enabled.
The RTX 4080 Super tells a similar story but with a smaller penalty. At PhysX High it averages 144 fps, which jumps to 254 fps with PhysX disabled. That is still a big performance hit at over 40 percent.
What is striking is not just the numbers but the visual difference. Disabling PhysX does not just slightly tone down effects. It strips away a lot of the atmosphere. Fog, smoke, fluttering debris, banners, cloth, particles and even elements of character models are either simplified or gone. The game looks flatter and emptier. It is clear why many players refused to just turn PhysX off, even when it wrecked their frame rates.
On RTX 50 series cards today, the reality is that Arkham Asylum is best played with PhysX disabled until Nvidia rolls out specific driver support in a future update.
Arkham City, New Drivers and a Dedicated PhysX GPU
Batman Arkham City offers an even better look at where RTX 50 series PhysX support is heading, because it is one of the first titles to receive dedicated handling in the new 591.44 driver.
On the older 581.29 driver, without that per game support, the RTX 5080 struggles when PhysX is set to High. It averages 84 fps with 41 fps 1 percent lows. Turn PhysX off and the same card hits 216 fps on average with 165 fps 1 percent lows. That is a performance loss of over 60 percent.
The RTX 4080 Super does much better with the same old driver. With PhysX High it averages 118 fps with 81 fps 1 percent lows, climbing to 153 and 122 fps respectively with PhysX disabled. That is still a notable 23 percent penalty but far less than what the RTX 5080 suffers.
In some scenes, the RTX 5080 can briefly overtake the RTX 4080 Super, but the moment heavy PhysX effects kick in the CPU becomes the bottleneck and the RTX 50 card drops hard, particularly in the final scene where it falls to an average of 41 fps while the RTX 4080 Super sails comfortably above 100 fps.
With the new 591.44 driver the situation improves. The RTX 5080’s average frame rate in Arkham City with PhysX High climbs from 84 fps to 96 fps, and the 1 percent lows leap from 41 fps to 71 fps. That is around a 14 percent average gain and a huge boost in smoothness. The game now holds above 60 fps even in the lows, making it feel much more playable, though the RTX 4080 Super still generally comes out ahead.
This suggests there is some overhead in the translation or compatibility layer Nvidia is using to support these older 32 bit PhysX titles on RTX 50 series hardware. Experience may vary from game to game, depending on exactly how PhysX is implemented.
Then there is the wild option: using a second GPU as a dedicated PhysX card. By installing both an RTX 5080 and an RTX 4080 Super in the same system and assigning the 4080 Super as the PhysX processor in Nvidia Control Panel, performance in Arkham City jumps again. The dual GPU setup averages 141 fps with 79 fps 1 percent lows on the latest driver, outpacing either card alone.
It is an over the top solution that requires lots of power, space and cooling, but it shows just how well hardware accelerated PhysX can still scale when you have the resources.
What This Means for PC Gamers
PhysX may be old tech but these tests show it still has a big impact on both visuals and performance in classic PC games. For RTX 50 series owners who enjoy older titles, a few key takeaways stand out.
- In some games, especially those without updated drivers, enabling PhysX can destroy frame rates as the CPU becomes the bottleneck.
- Turning PhysX off can massively boost performance but at a noticeable cost to visual richness and atmosphere.
- New Nvidia drivers with per game PhysX support can significantly improve performance and smoothness on RTX 50 cards, though RTX 40 series GPUs may still perform better in certain titles.
- If you have a spare Nvidia card lying around, using it as a dedicated PhysX GPU can still offer the best experience in some PhysX heavy classics.
Nvidia was always going to drop 32 bit support eventually, but it is encouraging to see the company making an effort to keep beloved PhysX showcase games playable on new hardware. The PC has always been the platform where old games can keep on living, and with some smart driver work and a bit of tinkering, even a relic like PhysX can still feel surprisingly modern.
Original article and image: https://www.pcgamer.com/hardware/graphics-cards/ive-tested-physx-now-that-its-sorta-supported-on-the-rtx-50-series-and-im-more-convinced-than-ever-its-a-feature-worth-fighting-for/
