I know the game is a bit old, but I just started playing rage 2 today and I was having fps problems. then I found that this game uses fidelityfx CAS so
Rage 2 review | TechRadar
We wanted to add our own spin to it" – How Avalanche is building a better open world wasteland in Rage 2 | GamesRadar+
Rage 2 Opening - 4K PC Gameplay on RTX 2080 Ti - YouTube