5/go X:\Users\Your username\Documents\Eidos\Batman Arkham Asylum\BmGame\Config, modify the UserGame.ini, change "PhysXLevel=0" to "PhysXLevel=1", change the "bAllowMultiThreadedShaderCompile=FALSE" to bAllowMultiThreadedShaderCompile=True", but the "True" vule is not fit to me, it brings slower fps on my Q6600.
save the UserGame.ini file.
6/go: X:\Program Files (x86)\Eidos\Batman Arkham Asylum\Engine\Config, modify the BaseGame.ini, after modification, the "[Engine.WorldInfo]" should looks like below:
7/go to x:\Program Files (x86)\Eidos\Batman Arkham Asylum\Binaries, run the BmLauncher.exe,here you can set the 3D options, but you already enable PhysX in Step 5, so leave it alone here, after setting, you can directly click "play" to star the game, or you can quit the setting window, and double click the BmStartApp.exe to start the game.
1/right now,this method needs further improvement, it can't work 100% perfect in the D2D version, but I can say ATi graphics cards will get fps more than 30fps in 75% area with PhysX on, compared with only 5-20fps before with PhysX on.
2/Due to the Securom DNA protection in the D2D version, at some points, the game will crach with PhysX on, Securom actually protects the PhysX effects!. So when you encounter the crach problem, just turn off the game, quit to the desktop, modify the UserGame.ini, change "PhysXLevel=1" to "PhysXLevel=0" according to the step 5, save the UserGame.ini file, run BmStartApp.exe to start the game again, play the game untill there's a Circle Circling at the lower right corner of the screen, that means it autosave the game, after the Circle disappears, you can quit the game, do step 5 again, to enable the physX, the run BmStartApp.exe to start the game with PhysX on.
3/at some places in the game with PhysX effects, such as flowing smoke, Liquid, shape changeable Spiderweb, you can find that after killed the enemies, just stand there without any actions and movements, the fps will gradually raise up.
Note that If you using the dedicated Nvidia PhysX Card will will work as well. As long as you use the Nvidia 197.xx with PhysX Mod Patch 1.02 or 1.03
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Yeah, NVIDIA "accidentally" released a version of its drivers with PhysX w/ ATI cards unlocked, then pulled them back and "fixed" the issue. You should still be able to find the unlocked drivers somewhere, which should save a lot of effort.