Batman: Arkham City's not out on PC in the UK until tomorrow, but already US players are reporting problems with the mouse and keyboard version.
Specifically, it's the Rocksteady title's DirectX 11 support that's causing problems, with multiple early bird players reporting a huge increase in performance when downgrading to an older version of DirectX.
Publisher Warner Bros has promised a patch on Arkham City's official forums, and offered advice on what to do.
We doubt the patch will arrive in time for tomorrow's UK release, so read up:
Instructions for changing DX 11 to DX 9 The Launcher can be accessed on Games for Windows LIVE and Steam to change DX 11 to DX 9 in the Settings menu. Change both DirectX 11 Features and DirectX 11 Tessellation to OFF. Games for Windows LIVE Start > All Programs > Games > Right click on Batman: Arkham City and select Launcher > Settings 1. Open the Start Menu 2. Select All Programs and then the Games folder 3. Right click on Batman: Arkham City and select Launcher 4. Choose Settings then click on the arrow next to DX options to change Steam: Launch Steam Client > Library > Right click on Batman: Arkham City > Configure PC Options 1. Open Steam 2. Select Library 3. Right click on Batman: Arkham City and select Configure PC Options 4. Choose Settings then click on the arrow next to DX options to change