I started playing arkham city last night. After getting the batsuit, tried different settings to see which one will get me 60fps consistent.
Finally I settled down with dx9 maxed and physX on Normal. 60fps consistent with an occassional dip to 45 fps when flying around. So i proceeded with the game.
Then when I came to the point where I have to rescue catwoman from two-face, where there a lot of thugs below. Frame rate suddenly dropped as low as 24fps and stayed there. Gpu usage by msi afterburner is 10-15%.
I cannot understand why this is happening. Tried lowering the settings from Very High -> Medium. Still the same results.
Anyone experienced this too? Or is this the only part of the game that slows down too much? Maybe others areas are fine.
As much as possible I would like to play this game 50-60fps. That is the reason I switched from console->PC.
Below are my specs:
CPU: Core i5 2500k @4.0ghz
GPU: Asus Gtx 580 direct cu 2. (290.36 Forceware)
Mem: G-skill ripjaws X 8gb
OS: Win 7 64 bit
Add'l info: I have the dx11 patch of arkham city already
The PC version of Arkham City as an absolute disaster. It's a complete mess that will probably take several rounds of patches to fix. Even with the initial patch, DX11 is still unplayable if you go into any outdoor area. The patch also apparently messed up DX9 performance for some people. You can try disabling physX as said above and see if that helps. Other than that, all you can do is wait for them to get the game working properly.
All I have to say is add rocksteady and WB games to the list of developers and publishers that you should not buy a PC game from on day 1, wait the 6 months they need to actually make a working PC game, or get the console version, that seems to be the only version they care about.