Protip: UE4 UI To Set Engine.ini console variables
I always grepped the source code or the DumpConsoleCommands console to find all the hidden UE4 console variables. Thanks to Nick Donaldson, I learned that there was a nice clean UI that UE4 exposed for this. Makes it really easy to set specific performance render config for different device profiles as well.
Go to Window>Dev Tools>Device Profile> Click the wrench widget to open it up