optiscaler-client-fsr4-manager

OptiScaler replaces DLSS by backing up the original nvngx_dlss.dll, then copying FSR4 wrapper DLLs (nvngx_dlss.dll and nvngx.dll) into the game's executable directory. The original files can be restored at any time from the .backup copies.

FSR4 settings are written to an nvngx.ini file in the game's directory, controlling preset (Ultra Performance through Ultra Quality), sharpness, frame generation, and low-latency mode. Profiles can be saved as JSON and auto-applied per game.

Yes, OptiScaler Client targets both Windows 11 and Linux, including Steam Deck compatibility. On Linux, configuration is stored in ~/.config/OptiScaler instead of %APPDATA%.

Crashes after patching usually stem from incompatible DLL wrappers or failed integrity checks. Restore the original by renaming nvngx_dlss.dll.backup back to nvngx_dlss.dll and deleting the OptiScaler nvngx.dll from the game directory.

Enable LowLatencyMode, RefreshRateBoost, and FramePacing in the INI's [Latency] section, and set MinFPSThreshold so frame generation only activates above roughly 40 FPS. AsyncCompute can further reduce latency by overlapping GPU work.

DLL patching requires write access to game installation directories, which often need administrator rights. The client checks for elevated privileges via WindowsPrincipal and can restart itself with the runas verb to request elevation.