AMD FSR 4 remains limited to RDNA 4, at least officially
AMD has no updates to share, shares HardwareUnboxed.
AMD still has not shipped an official FSR 4 option for older Radeon GPUs, even though the company has already accidentally shown a working path for non-RDNA 4 hardware. Today, AMD’s own documentation keeps FSR 4 locked to Radeon RX 9000 series cards, with the FSR API falling back to FSR 3.1.5 on anything else.
That lock has always come with a clear technical justification. AMD says FSR 4 relies on hardware-accelerated FP8 Wave Matrix Multiply Accumulate on RDNA 4, which is not available on earlier Radeon architectures. That is similar to how NVIDIA has historically tied DLSS features to Tensor hardware generations.
The company’s most recent statement on this is from the new HardwareUnboxed video:
Source: HardwareUnboxed
But we know FSR4 INT8 exists
The problem is that AMD also leaked evidence that it has been building a second implementation designed to run without FP8. In August 2025, AMD briefly published FSR 4 source code as part of the FidelityFX SDK 2.0 release, then pulled it back, but the files had already circulated and were reviewed publicly.
The leak didn’t change official support, but community builds based on that leak put AMD in an even tougher spot, because they turned “theoretical” into “it runs.”Review channels published testing of an INT8 build running on RDNA 3 and even RDNA 2 , using the FSR 3.1 style DLL swap workflow in supported titles. Their conclusion was that image quality moved forward versus FSR 3.1, with a performance cost that varies by GPU and game.
FSR4 Performance impact on RDNA3/4 GPUs, Source: ComputerBase
An AMD exec recently said the company had cut the line on newer Redstone features to avoid a poor experience on older GPUs, while still leaving room for a scaled approach later. That same logic fits FSR 4 INT8, because once AMD enables it officially, the company will have to face questions from gamers about why this technology runs differently on some systems. However, they did, keep doors open for a possible FSR4-Lite approach, but we heard nothing about this since CES.
With RX 9000 series prices climbing, keeping FSR 4 exclusive limits how many players can use it, which affects how much developers prioritize clean FSR 3.1 integrations that the driver can upgrade. AMD’s own notes also show the driver-level upgrade path has API constraints, it only applies to DirectX 12 games that integrated a signed FSR 3.1 DLL correctly, and it does not even cover Vulkan titles, which many gamers often mention.
I will add that, of course, we did reach out to AMD on this subject. We asked specifically about supporting FSR4 on RDAN2 and RDNA3 cards back in September. AMD has never responded, even with a short statement.
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