It appears that AMD has ruled out extending FSR 4 support to previous-generation GPUs.

According to reports from VideoCardz, an FSR 4 DLL file was discovered in unofficial Radeon drivers, prompting further speculation about its compatibility.

Tech analyst Osvaldo Pinali Doederlein revealed on X that FSR 4 employs a machine-learning algorithm that relies on an 8-point floating-point (FP8) implementation.

Furthermore, RDNA 4 GPUs are expected to feature FP8 WMMA (Wave Matrix Multiply Accumulate), a technology designed to accelerate AI-based applications, which appears to be a core requirement for FSR 4’s functionality.

This technical dependency means that RDNA 3 GPUs, such as the RX 7900 series, may not receive full FP8 WMMA optimisation, while RDNA 2 GPUs are unlikely to support FP8. As a result, older AMD GPUs will miss out on FSR 4’s performance-boosting features.

With Nvidia’s rival DLSS 4 upscaling technology set to be available across all RTX GPUs, AMD’s decision to limit FSR 4 compatibility could drive some users towards Team Green’s offerings. This exclusivity may alienate some long-time AMD users who were hoping for broader support across different GPU generations.

The lack of FSR 4 support for RDNA 3 raises concerns about its implications for upcoming handheld gaming PCs. Devices such as the Lenovo Legion Go 2, which is expected to feature Ryzen Z2 Extreme APUs built on RDNA 3.5 architecture, may not be able to leverage AMD’s latest frame generation technology.