FSR is AMD’s equivalent of Nvidia’s DLSS, a suite of technologies that dynamically upscales images from a lower baseline resolution to match your screen’s native resolution. It basically takes some of the pressure off your GPU for running games at higher resolutions, enabling you to play with improved settings or a smoother framerate with minor impact on image quality. It can also help compensate for particularly demanding graphics tech like real-time ray-tracing.
FSR 2.0 offers a notable improvement over FSR 1.0, with the switch from spatial upscaling to temporal upscaling (which upscales the image based on data from multiple frames), bringing it much closer to the performance of Nvidia’s hitherto superior DLSS tech. FSR can also be used with a much wider array of GPUs than DLSS, which requires you to own an RTX 20-series or better card. FSR 2.0 is more demanding than the previous version, however, with AMD recommending an RX 5700 XT or 6700 XT for 4k gaming, or a 6500XT for throwing axes at people in 1080p. You can read a more detailed breakdown of how FSR works in this article.
I’m a big fan of upscaling tech. With graphics cards still being ludicrously expensive (although you can actually buy them now, which is something), DLSS and FSR can help to extend the lifespan of your current rig – particularly the latter, as it isn’t bound to a limited number of GPUs. That said, God of War is only the third game so far to add support for FSR 2.0, preceded by Deathloop and, weirdly, Farming Simulator 22. So it’s not that useful yet, although several more games are pipped to include the option soon, including Microsoft Flight Simulator, Forspoken, Grounded, and EVE Online.