FSR 4 now runs on older GPUs thanks to leaked AMD source code

Leaked AMD source code brings FSR 4 to Radeon RX 7000 and GeForce RTX 30

HARDWARE NEWS manhkbrady - Sep 17, 2025, 03:00

AMD’s FSR 4 upscaling technology is exclusively compatible with the company's RDNA 4 graphics cards. Therefore, gamers on PC need to have the RX 9000 series (RDNA 4) GPUs to take advantage of AMD's latest AI upscaler. However, modding enthusiasts have found a way around this restriction by utilizing leaked source code for FSR 4 to allow support on older graphics cards. This includes AMD's RX 7000 series GPUs as well as Nvidia’s RTX 30 series GPUs.

How did this come about? AMD inadvertently released an INT8 (8-bit Integer) version of FSR 4 in conjunction with its FidelityFX SDK 2.0. Although AMD swiftly removed these files, backups were already made. With these files, the Reddit community has constructed a new FSR 4 DLL, enabling the use of FSR 4 on GPUs that do not employ RDNA 4 architecture.

Some people apparently got FSR 4 working on RDNA3 GPUs under Windows (previously it was possible under Linux). It seems to work fine for this user in Cyberpunk 2077 with an RX 7900 XTX: https://t.co/pdtJXb5Gxb
— Sebastian Castellanos (@Sebasti66855537) September 15, 2025

According to user feedback, this new iteration of FSR 4 provides superior visual quality compared to FSR 3.1. Nevertheless, it is important to mention that FSR 4 operates at a slower rate than FSR 3. Reports from Bedony FPS indicate a 7% performance difference. Additionally, some users have noticed graphical artifacts and aliasing in certain games. It is evident that there are reasons AMD has not made FSR 4 available for non-RDNA 4 GPUs at this time.

I got it working, 7% performance delta in CP77 at 1440P with FSR in quality

FSR cost went from 0.4ms to 1.2ms - ish @Sebasti66855537
— Beyond FPS (@beyond_fps) September 15, 2025

Players have effectively activated AMD’s FSR 4 upscaler on both RX 7000 series and RTX 30/40 series GPUs. While this upscaling solution is not free from problems, it demonstrates the feasibility of bringing FSR 4 support to RDNA 3 graphics cards for AMD.

As anticipation grows for AMD’s forthcoming RDNA 5 GPUs, you don’t need to wait to enjoy high-quality gaming experiences. The Radeon RX 9070 XT, which is designed on RDNA 4 architecture and features 16GB of VRAM, already offers outstanding performance, stunning visuals, and efficient power consumption for the most demanding gaming titles available today. As always, for the latest news on hardware launches and industry developments, be sure to follow our dedicated hardware coverage.