Quote Originally Posted by zanzabar View Post
go to "Documents\Eidos\Batman Arkham Asylum Demo\BmGame\Config"

then open UserEngine.ini

next change "PhysXLevel=0" to "PhysXLevel=1", u can also set it to 2 but it just seams to add alot of paper and that makes it lagg a little while adding nothing to the game
Some other people have been trying out PhysX on the CPU through the in-game menu & are getting as low as 12 fps.

Are you sure your fps did not dip into the 12's ?