Overview

• Users report that importing AMD FidelityFX SDK 2.0 files into DLSS Swapper and renaming amd_fidelityfx_upscaler_dx12.dll to amd_fidelityfx_dx12.dll can expose FSR 4 in titles that ship with FSR 3.1.
• The swap applies only to games that already support FSR 3.1, and true FSR 4 operation requires Radeon RX 9000-series GPUs, with older cards falling back to FSR 3.1.5.
• A GitHub screenshot from Horizon Zero Dawn: Remastered shows the graphics menu reporting FSR 4.0.2 after the file replacement.
• Coverage notes uncertainty over whether games are actually running FSR 4 versus only displaying the DLL version, alongside Linux triggering issues and the method’s unofficial, mod-like status.
• The technique echoes long-standing DLSS DLL upgrades and is likely to be a stopgap until AMD’s Adrenalin software delivers FSR 4 support in select titles.