AMD FSR 4 Spotted in Adrenalin Driver: Exclusive Support for RDNA 4 GPUs Confirmed

A clue about AMD FSR 4 appears to have been discovered in a Preview version of the Adrenalin driver, hinting that the new technology might be exclusively linked to the RDNA 4 architecture. However, there is no official confirmation yet.
The idea that AMD’s new upscaling system could be tied solely to the RDNA 4 architecture, specifically to the Radeon FX 9070 series, has been circulating for some time. Still, there is room for doubt since AMD had previously suggested the possibility of extending compatibility to specific models from other GPU series during the announcement of FSR 4.
The details emerging from the DLL file analysis seem to reinforce the notion that FSR 4 will be restricted to newer AMD graphics card models due to specific technical limitations, bringing back the earlier belief of exclusivity.
Technical Limitations
According to a report by VideoCardz, analyzed by Osvaldo Pinali Doederlein, FSR 4.0 appears to require significantly more memory than its predecessors, jumping from 6.5 MB to 17 MB in terms of usage for FidelityFX Super Resolution.
FSR 4 reportedly uses a machine learning algorithm based on 8-bit floating-point calculations. This necessitates support for WMMA (Wave Matrix Multiply Accumulate), which enables such precision. Consequently, only GPUs based on RDNA 4 architecture would be capable of supporting this level of processing, effectively ruling out older AMD graphics cards.
At the same time, there is speculation that FSR 4 could be immediately available for many games, possibly through enhancements in FSR 3.1, paving the way for broader implementation despite hardware limitations.