Test:
Results:  84 FPS
Settings:  Vsync Off, Default w/all options Off, Environmental Slider = none, Clipboard away
Location:  Tower A1, CraterMA
Edited:  There was 3 fps gain from putting Clipboard away.  Note*  FOV was 90 (~77 fps); default FOV 80 (~84 FPS!)
All in all, 10 fps gained from putting clipboard away and using default field of view.