AMD has shown a passing interest in bringing its FSR 4 upscaler to RDNA 3 GPUs but there’s seemingly been no progress on that front. In lieu of official support, modders have taken up the task of backporting the feature themselves. These efforts have borne fruit and Radeon RX 7000 Series owners are now one step closer to joining the AI upscaled party.
Reddit user Virtual-Cobbler-9930 has shared screenshots of FSR 4 running on their Radeon RX 7900 XTX, as well as some performance analysis. Since RDNA 3 GPUs can’t swap FSR versions through AMD Software unlike their RDNA 4 successors, the user turned to Optiscaler and some launch parameters for a workaround.
In Cyberpunk 2077 for example, Virtual-Cobbler-9930 shared that FSR 4 produced superior edge quality and image stability. The user highlights the fidelity of bushes, grass, and trees is noticeably better, with less noticeable smearing. This echoes Sam’s analysis of the upscaler in our Radeon RX 9070 XT review.
These improvements don’t come without cost, unfortunately. While the game ran at 85fps using FSR 3.1, frame rates tumbled down to 56fps with FSR 4. This drop in performance likely stems from RDNA 3’s AI accelerators, which simply aren’t as powerful as RDNA 4’s. You can trigger similar behaviours by using the DLSS Transformer model on RTX 40 Series GPUs and older too. Even so, using FSR 4 still resulted in frame rates higher than native 4K rendering and superior image quality to FSR 3.1.
Moving to Oblivion, the Redditor saw between 20-30% performance hit after upgrading to FSR 4, but the quality was apparently worth the cost. FSR 4 alleviated noticeable smearing from sword swinging, which is understandably very distracting in a game like this. That said, FSR 4 did also introduce some weird artifacts on the trees, even though it was more stable overall than FSR 3.1.
However, an issue that will likely deter most users from trying this mode is how poorly it scales at lower resolution. Virtual-Cobbler-9930 indicates that this FSR 4 mod runs best in quality mode, as anything lower doesn’t net much improvement. The question becomes whether you’re willing to put up with a smaller boost in frame rate in service of higher image quality.
It’s worth remembering that this is just a mod and an official implementation should hopefully result in better performance while maintaining the higher levels of fidelity FSR 4 offers. However, speaking as an owner of an RDNA 3 GPU, I’d welcome the choice between upscalers regardless of performance.
Hopefully this pushes AMD to speed up support for FSR 4 on Radeon RX 7000 Series GPUs, as it’s clearly possible. After all, this mod has only shown to be working on Linux for the moment. As soon as Windows support rolls around, though, I’ll be downloading it pronto.
