Fortnite, what changes PRO
The file
%LOCALAPPDATA%\FortniteGame\Saved\Config\WindowsClient\GameUserSettings.ini
What changes
- V-Sync and motion blur off
- Grass hidden
- Shadows, global illumination, reflections, post-processing, effects, foliage and shading at the minimum
- Textures on High
- The FPS limit you choose, also matching the monitor's refresh rate
Good to know
- The file stays read-only, so what you change in the game doesn't stay until you restore it.
How to go back
Before changing the file the app saves a copy. Restore puts it back as it was, even if the subscription has ended.
With Game Mode
While the game is open the app puts the power plan at the top, raises the process priority and, on hybrid CPUs, picks the cores it can use. When you close it, everything goes back to how it was. It works with the app open, even minimised to the tray, and the app can start by itself with Windows.
Anti-cheat
The config only changes the file, which the game reads by itself. Game Mode changes the process priority from outside and, on hybrid CPUs, the cores it can use, as you can do from Task Manager. The app doesn't read or change game memory and doesn't inject anything. Nobody but the people who make the game can guarantee what its anti-cheat accepts.
What about FPS?
You won't find a promised number here, because what you gain depends on the game and the PC.