How to unlock FPS in Batman: Arkham Knight

(First, you need to log into the game at least once)

1). Go to the game's folder (where it is installed) and open the following directories:
...\Steam\steamapps\common\Batman Arkham Knight\BMGame\Config

2). Find the file named BmSystemSettings.ini

3). Open it using Notepad or any other text editor

4). Find the parameter: MaxFPS=
(To search for text in Notepad, press Ctrl+F and enter the text there.)

5). Change the value (it will be 30, 60, or 90 depending on the current game setting) to the desired one (for example, 144 or 240 to match your monitor's refresh rate).

6). Save the changes in the file (File -> Save or Ctrl+S) for them to take effect.

After this, the FPS in the game will not be limited to 30-90 frames per second.

For anyone planning to play the full Batman trilogy, these guides may be useful
https://steamcommunity.com/sharedfiles/filedetails/?id=3582729584
https://steamcommunity.com/sharedfiles/filedetails/?id=3580726217

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