AMD’s FSR 4 has always been a DirectX 12-only affair, locking out Vulkan users—until now. A fresh test build of OptiScaler (version 0.9.0-pre10) has added Vulkan support for FSR 4, effectively bypassing AMD’s restrictions. The trick? A compatibility layer that translates Vulkan calls into DX12, much like DXVK or VKD3D handle DirectX on Linux. This means FSR 4’s Redstone frame generation could soon work on Vulkan-based games, including those running on Linux.
For Linux gamers, this is a double-edged sword. While Vulkan often delivers better performance than DX12 on Linux, FSR 4 with DX12 still struggles due to a Mesa-related issue the OptiScaler team can’t resolve. The developers have explicitly stated they won’t chase fixes for problems outside their control, leaving DX12 on Linux in limbo.
The new build also retains support for FSR 2.1 in Vulkan, ensuring older AMD GPUs (like RDNA 1/2) can still benefit from upscaling—though FSR 4 remains the star feature.
What’s Changing?
- Vulkan FSR 4: Now compatible with Vulkan-based games, expanding beyond DX12 exclusivity.
- Linux Support: Vulkan games on Linux can access FSR 4, but DX12 remains broken due to Mesa limitations.
- FSR 2.1: Still supported in Vulkan, ensuring backward compatibility for older GPUs.
- No DX12 Fixes: The team won’t address Linux DX12 issues tied to Mesa, leaving them unresolved.
- Test Build: Current version (0.9.0-pre10) is experimental—use with caution.
This move could push more Vulkan games to adopt FSR 4, especially if developers prioritize cross-platform compatibility. However, Linux DX12 users are left waiting for Mesa to catch up—something OptiScaler can’t force.
For now, the update is a win for Vulkan gamers, but the broader ecosystem still faces fragmentation between DX12 and Vulkan performance on Linux.
