Proton-CachyOS just fixed a specific but useful OptiScaler problem for people trying to use DLSS inputs with FSR4 upgrades on Linux.
• GitHub issue #214 was a feature request for Proton-CachyOS
• Problem involved using PROTON_USE_OPTISCALER=1 with PROTON_FSR4_RDNA3_UPGRADE=1
• Some games that only expose DLSS inputs, like Control Ultimate Edition, were not creating the needed DLSS DLL files
• Missing files included nvngx_dlss.dll, nvngx_dlssd.dll, and nvngx_dlssg.dll
• Without those files, OptiScaler could not hook the DLSS input and upgrade it to FSR4
• The workaround was launching once with only PROTON_USE_OPTISCALER=1, then relaunching with the FSR4 upgrade flag
• Proton-CachyOS 11.0-20260601 changed PROTON_USE_OPTISCALER to also download DLSS DLLs by default for FSR4 input support
• The same release also added PROTON_OPTISCALER_CONFIG for editing OptiScaler config through an environment variable
• This is niche, but it matters for Linux gaming, AMD users, and people testing FSR4 upgrade paths through Proton-CachyOS
This is one of those Linux gaming updates that sounds easy to ignore to normal people, but it will making gaming much more comfortable.
Before this, if you wanted to use OptiScaler with FSR4 upgrades in a DLSS-only game, you had to do the dummy launch for a game to workaround just to generate the DLSS DLL files.