I want to reduce GPU usage because I use the computer where I mine. I suppose this is done with the -f option, but I can't find any documentation for it (except "target execution timing"). What sort of values should be used here?
It's a matter of preference but here is the values I use.
-f 30 for browsing
-f 60 for HD video
-f 240 for games
It's also a good idea to disable flash acceleration and aero.