Shader Pre-Caching allows Steam to download pre-compiled GPU shaders matching your system configuration. […] If enabled, Steam will collect shaders from your system when needed.
It’ll download shaders matching your card+driver and (if you’re the first with that specific config) upload your own compiled shaders for others to use.
It’s in Options - Downloads - Shader Pre-Caching.
It’ll download shaders matching your card+driver and (if you’re the first with that specific config) upload your own compiled shaders for others to use.