AMD on FSR 4 for RDNA 3 and Older GPUs: “No Updates to Share at This Time.”

AMD’s FidelityFX Super Resolution 4 technology, now known simply as FSR 4, is currently supported in many games, but not across all AMD RDNA GPU generations. In response to an inquiry from Hardware Unboxed, AMD mentioned that it is still uncertain whether official FSR 4 support will be extended to the Radeon RX 7000 series and older GPUs, as the company reportedly has “no updates to share at this time.” AMD official product separation stems from its RDNA 4 architecture and the support for 8-bit floating point instructions. While the latest RDNA 4 hardware supports Wave Matrix Multiply Accumulate in FP8 format, older RDNA generations like RDNA 3 and RDNA 2 lack this hardware instruction support and can’t process 8-bit floating point data in this format.

However, older Radeon GPUs can instead rely on the 8-bit integer (INT8) data formats, which Radeon RX 7000 series fully supports. AMD accidentally leaked FSR 4 INT8 on its AMD GPUOpen platform, showing that FSR 4 on older GPUs is a possibility, which is just kept hidden for now. Later on, ComputerBase tested this leaked library, finding that FSR 4 offers a balance between native image quality and FSR 3.1 performance on both RDNA 3 and RDNA 2 hardware. In tests with Cyberpunk 2077 in 4K on Ultra settings using the AMD Radeon RX 7900 XTX, FSR 4 delivered 11% faster performance than native, but was 16% slower than FSR 3.1. Interestingly, performance may be the reason why AMD is holding these INT8 FPR 4 libraries back, but another point could be product separation.

AMD already segregates its latest FSR “Redstone” suite of technologies, with features like Ray Regeneration and Radiance Caching exclusive to RDNA 4 hardware in the Radeon RX 9000 series of GPUs. Other basic technologies like upscaling and frame generation are supported on older RDNA 3/2/1 generations, but use an FSR 3.1 Fallback, with no FSR 4 support for now. However, since INT8-based FSR 4 exists, it may only be a matter of time before the company releases the capability to older GPUs, but the expected performance might not be there.