AMD planned RDNA 3 support for July, but Valve may have pushed the files early
FSR 4.1 file works with RDNA 3 and RDNA 3.5 GPUs
Valve appears to have pushed an early FSR 4.1 build through Proton Experimental. The file was spotted in the Proton Experimental depot, but the manifest was reportedly removed shortly after it appeared.
That may explain why the file could not be downloaded through Steam Console earlier when I was preparing our previous post . The depot was visible, but access to the specific manifest did not work. Luckily, some people managed to download it just in time.
Valve leaked FSR 4.1 INT8
According to a post on the Radeon subreddit, one user managed to download the manifest before Valve removed it. The post claims the leaked file is “FSR 4.1.1 Int8” and includes “ amdxcffx64.dll. ” The same post says the file is signed, which should make it usable in games that check DLL signatures.
The leak is interesting because AMD has already confirmed FSR 4.1 support for RDNA 3 GPUs, including Radeon RX 7000 series cards, for July. RDNA 2 support is planned later, with AMD targeting early 2027 for Radeon RX 6000 series and other RDNA 2 products.
Source: Reddit
The timing suggests that Valve may already be preparing Proton support for AMD’s upcoming rollout. It also suggests that the RDNA 3 version is far enough along to appear in a public Proton Experimental depot, even if that release was not intended to go live yet.
Works with Radeon 890M (RDNA3.5 iGPU)
More importantly, the leaked build works on RDNA 3.5 hardware (from the screenshot we can see Radeon 890M iGPU). That would include integrated GPUs used by newer Ryzen AI and handheld-class processors, although AMD has not officially committed to FSR 4.1 support for RDNA 3.5. AMD previously gave mixed signals on that topic.
Source: Reddit
For RDNA 3 users, this may simply be an early look at the July update. For RDNA 3.5 users, it is more interesting because it shows the INT8 path can apparently run on this architecture, at least through community testing.
So what this means, you can download and use FSR4.1 INT8 just as you did with FSR4 INT8. Or you can just wait for official release, which will give you full support through official (Windows) drivers. For this this is only useful for Linux users, modders and enthusiasts.
