Turn physX on in BATMAN AA

Soldato
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Not tried it in the full game but in the demo you just turned it on in the launcher. Crippled the frame rate though, even on my 4870x2.

I don't see the option to turn it on.

k9hyrc.jpg


These settings give me a constant 50-60 fps. I tried everything maxed out but the frame dipped to 20-30. :(
 
Soldato
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You can turn it on with any card, but if you're using ATI it'll do the calculations on your CPU and kill framerates.

That's because it not using the power of the CPU & is running single thread & will only use one core even on an i7.

Ok, so it's hard to see, but Task Manager is showing CPU utilization of 14%, which means the game—and Nvidia's purportedly multithreaded PhysX solver—is making use of just over one of our Core i7-965 Extreme's eight front-ends and less than one of its four cores. I'd say that in this situation, failing to make use of the CPU power available amounts to sabotaging performance on your competition's hardware. The truth is that rigid-body physics isn't too terribly hard to do on a modern CPU, even with lots of objects. Nvidia may not wish to port is PhysX solver to the Radeon, even though a GPU like Cypress is more than capable of handling the job. That's a shame, yet one can understand the business reasons. But if Nvidia is going to pay game developers to incorporate PhysX support into their games, it ought to work in good faith to optimize for the various processors available to it. At a very basic level, threading your easily parallelizable CPU-based PhysX solver should be part of that work, in my view.
http://www.rage3d.com/board/showthread.php?t=33953012
http://techreport.com/articles.x/17618/13

Batman Game Play with CPU PhysX all cores trick
Because a Core i7 is more than capable enough of handling PhysX by itself (this is what the tweak does). It allows ALL Cores to be used for PhysX (nVIDIA.. in an attempt to try and claim CPUs can't run PhysX... generally relegate it to a single core). In fact a Core i7 is nearly as powerful (GFLOP wise) in double precision mode as an nVIDIA GT200b Graphics card: http://www.realworldtech.com/page.cf...WT090909050230. A Nehalen Architecture based CPU is capable of around 102GFLOP in single precision (stock) and 55GFLOP is Double Precision while a GT200b based nVIDIA GPU can handle 622-933GFLOP in single precision and 77GFLOP in Double Precision. My understanding of PhysX is that it uses quite a lot of Double Precision calculations (to calculate physical interactions). So on that front they're quite close in performance. This also explains why enablong CPU PhysX (using the tweak) results in all of the PhysX effect while remaining playable.

I'm playing the game with PhysX turned on (since nvIDIA won't allow me to use the 9800GT anymore for dedicated PhysX) and it's entirely playable (I haven't seen it dip bellow 30FPS with ALL the PhysX candy turned on). To prove the point I will upload an HD video on YouTube... keep in mind I am ALSO recording while handling PhysX and the game.. so the CPU is under a lot of pressure yet does it all effortlessly.
 
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Soldato
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Is it better to use the CPU to calculate the PhysX or leave it to the GPU? I'm running a Quad 6600 G0 @ 3.2Ghz and an 768mb 8800GTX, not sure if it would be better to shift it from the gfx card to the CPU or not, running 1920x1280.
 
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