I have noticed that my laptop with a Nvidia GT 540M stuttered quite a bit during Diablo 3. Someone on the Diablo Forums have posted a fix and it has done wonders. It raised my FPS 40 to 60.
- Go to your Documents folder.
My path on Windows 7 looks like this C:\Users\Mike\Documents
- Find the Diablo 3 folder and open D3Prefs.txt.
- Find HardwareClass (line 39) and change the “4” to “1”.
Note: Diablo 3’s show fps command is Ctrl+R.