Showcased in Cyberpunk 2077, FSR 4 still substantially improves the image on older GPUs, but with a notable performance cost.
Yesterday on Reddit, intrepid user u/AthleteDependent926 posted a bombshell to the r/Radeon subreddit: AMD’s FSR 4 source code leak in August contained all the files needed to run FSR 4 with older GPU hardware. Doing so requires the use of OptiScaler, which we previously covered allowing users to enable FSR 4 in games that only supported DLSS or XeSS. That was for GPUs that already had AMD FSR 4 support, though; now, the floodgates are open for any user with a graphics card supporting INT8 calculations, a category that includes both AMD’s RDNA 2 and RDNA 3 GPUs, as well as Intel’s Arc and NVIDIA’s GeForce RTX GPUs.
While the source code that AMD accidentally released included an INT8 version of the FSR4 model—it normally uses the FP8 format that is only supported by RDNA 4—it was just source code, which means that it wasn’t in a form that users could actually make use of. Redditor u/AthleteDependent926 took the time to compile the source to a functional .
