Easy performance boost and fix for most problems in GTA San Andreas The Definitive Edition.(works on all three definitive edition titles)
GTA: San Andreas Definitive Edition FPS Problems / Lag FIX
- Open your Steam Library
- Right click the game’s title and select Properties
- On the General tab you’ll find Launch Options section.
- Enter the launch options you wish to apply and just add “-dx12″ (without ” “).
- Close the game’s Properties window and launch the game.

Note: Your GPU needs to support dx12.(almost every gpu does support it)
FPS BOOST SETTINGS
Biggest impact on performance:
- Car reflections: set to “screen”
This almost doubled my FPS.
Some Smaller Impacts:
- Visual effects: set from “Ultra” to “High” (almost no visual difference)
- Cloud quality: set to “Volumetric” (almost no visual difference)
- World shadow quality: set to “medium” (has a visual impact)
- Streetlight quality: set to “medium” (has a visual impact)
- Vehicle light quality : set to “medium” or “low” (has a visual impact)