Note: The render resolution HAS to be below 1.0 in order for FSR's upscaling to work, otherwise you would only get its anti-aliasing function without the performance gain. FSR isn't perfect however. If you want quality anti-aliasing I'd suggest using override settings in your graphics card's utility software (GeForce Experience/Radeon Software), if it's any better, that is.
Edit: This video was made before they returned the SMAA option, so ignore my previous tip and use SMAA instead.
0:00 Settings
0:02 Normal Terrain
1:02 Graphically-Intensive Terrain
2:02 Combat - Overworld
2:28 Combat - Domain
3:02 Conclusion