YouTuber shows Vega GPU running FSR 4 with experimental build of OptiScaler and leaked Proton version of FSR 4.1.1

Q: Which games tested in the video failed to run with the FSR 4.1.1 mod and were there any error messages or workarounds shown?

Control and Pragmata failed to work. The article does not report any error messages or show any workarounds for those failures.

Q: How did FSR 4.1.1 performance on the MI50 compare to FSR 4.0.2c across different presets (quality/balanced/performance) in the benchmarks shown?

FSR 4.1.1 delivered better performance than FSR 4.0.2c on the MI50 across the shown presets. In Cyberpunk 2077 balanced mode the MI50 hit 69 FPS with FSR 4.1.1 versus 64 FPS with FSR 4.0.2c, and in Alters balanced mode it reached 90 FPS with FSR 4.1.1 versus 83 FPS with FSR 4.0.2c.

Q: Does the Proton leaked build of FSR 4.1.1 used in the video require any special Proton/Wine settings to function on Linux, or was it demonstrated on Windows?

The article says the YouTuber used the leaked Proton version of FSR 4.1.1 along with an experimental OptiScaler and a small tweak to OptiScaler's configuration to bypass a new detection mechanism, but it does not state whether the demonstration ran on Windows or required special Proton/Wine settings on Linux. This question cannot be answered from this article.

YouTuber mods FSR 4.1.1 to work on AMD's Instinct MI50 Vega-based datacenter GPU, and benchmarks the GPU against FSR 4.0.2c in games like Cyberpunk 2077.

Aaron Klotz

Tech Reporter

Published Jul 5, 2026 8:10 AM CDT

2 minutes & 15 seconds read time

TL;DR: A YouTuber successfully ran FSR 4.1.1 on an AMD Instinct MI50 Vega GPU using a leaked Proton version and an experimental OptiScaler, achieving better performance than FSR 4.0.2c in some games. This mod likely only works on enterprise Vega GPUs due to hardware INT8 support limitations.

Voice: DefaultSpeed

0:00 / 3:39

Someone has figured out a way to get FSR 4.1.1 working on AMD's Vega architecture, despite FSR 4 only being supported on RDNA 3 and RDNA 4 GPUs at the time of writing. YouTube channel yoyosan published a video showing FSR 4.1.1 working on an AMD Instinct MI50 GPU from 2018 with better performance than FSR 4.0.2c.

The YouTuber stated that a few things had to come together for them to get FSR 4.1.1 running at all on the Vega GPU. The version of FSR they used was the Proton version of FSR 4.1.1, which was leaked several days ago. Furthermore, an experimental version of OptiScaler was also required that was not available to the public and was only accessible from the OptiScaler developer's Discord server. The main hurdle the YouTuber had to overcome was a new detection mechanism built into FSR 4.1.1 that disables the latest model if an unsupported GPU is detected. Outgoing iterations of OptiScaler can't turn this off, but the newer experimental one the YouTuber downloaded from the OptiScaler developer's Discord server can with a small tweak to the tool's configuration file.

In games that worked, FSR 4.1.1 was stable on the YouTuber's Vega-based Instinct MI50 graphics card while offering superior performance to FSR 4.0.2c. In Cyberpunk 2077, the GPU achieved 69 FPS with FSR 4.1.1 set to balanced mode and 64 FPS with FSR 4.2.0c at the same settings. Alters with FSR 4.1.1 set to balanced mode achieved 90 FPS and 83 FPS with FSR 4.0.2c. Control and Pragmata were two other games the YouTuber tested but failed to work.

Read more: AMD's new FSR 4.1 for RDNA 3 also works on RDNA 3.5 and RDNA 2 GPUs
Read more: FSR 4.1 support for RX 7000 GPUs arrives ahead of schedule with new Adrenalin driver update
Read more: RadeonTuner enables unofficial FSR 4 driver injection in games with RDNA 3.5 iGPUs

Sadly, this FSR 4 mod will likely only ever work on enterprise iterations of AMD's Vega GPUs; AMD only implemented INT8 hardware support into its datacenter Vega-based GPUs, and bypassed the feature on its consumer versions of its Vega GPUs. Technically, Radeon cards with the Vega architecture can simulate INT8, but there's no guarantee that doing so on these GPUs provides enough performance to run FSR4 upscaling well enough to outperform native rendering.

Frequently Asked Questions

TweakBot answers common questions about this news using TweakTown's own coverage from this page and related content from our archive. Tap a question to reveal the answer, or type your own below.

Question #1

Can the OptiScaler experimental tweak used to bypass FSR 4.1.1's GPU detection be applied on consumer Vega Radeon cards or only on datacenter Instinct MI50 units?

The experimental OptiScaler tweak was used on an AMD Instinct MI50 datacenter Vega GPU, and the article says this FSR 4 mod will likely only work on enterprise iterations of Vega because AMD implemented INT8 hardware support only in its datacenter Vega GPUs. Consumer Vega Radeon cards lack that INT8 hardware support, so the tweak is unlikely to work well on them.

Answered

Question #2

Which games tested in the video failed to run with the FSR 4.1.1 mod and were there any error messages or workarounds shown?

Click to reveal answer

Question #3

How did FSR 4.1.1 performance on the MI50 compare to FSR 4.0.2c across different presets (quality/balanced/performance) in the benchmarks shown?

Click to reveal answer

Question #4

Does the Proton leaked build of FSR 4.1.1 used in the video require any special Proton/Wine settings to function on Linux, or was it demonstrated on Windows?

Click to reveal answer

Have a question not listed here? Ask below and TweakBot will answer it.

Still, seeing FSR 4 on a Vega GPU at all gives us an idea of what a GPU such as Vega 64 might have been capable of with FSR 4 in another timeline where AMD baked hardware support for INT8 into its gaming Vega-based GPUs. As a reminder, AMD only provides FSR 4 in INT8 and FP8 formats for its various GPUs, with FP8 being its most performant version of FSR 4 that is exclusive to RDNA 4 GPUs. AMD is actively working on FSR 4 support for RDNA 2 and RDNA 3/3.5 iGPUs, with the former getting FSR 4 support in 2027.