What is AMD FidelityFX Super Resolution (FSR)?
iRacing supports resolution scaling through AMD's FidelityFX Super Resolution (FSR). Resolution scaling allows the sim to be rendered at a lower resolution to save on processing requirements, but then be scaled to fit the correct output resolution. This produces an image with lower quality than without the feature, but will require less processing power from the graphics card. This feature will not reduce the CPU load of the sim.
Even though this is an AMD feature, this is usable by both AMD and NVIDIA cards.
Using FSR in iRacing
To activate this feature, enter the sim, go to the Options screen, and then select the Graphics tab. This feature requires a restart of the sim before it takes effect.
Arrow #1 is where you select the mode. AMD FSR has four possible modes of operation:
Ultra mode will give the highest quality with the smallest performance increase. Subsequent modes will give lower quality, but more performance increase.
Resolution scaling will only function when an Anti-Aliasing mode is active (AA) and these settings are marked by the #2 and #3 arrows. Either #2 needs to be set to a value higher than 0x, or #3 needs to be set to SMAA or FXAA. Once one or both of these are set and the mode is selected FSR will be active the next time the sim starts.