Are you on Windows 10? If so, can you rearrange your start menu/screen icons? The latest driver messed this up for me, I went back to the previous driver (373.06).
Just a quick heads up. Nvidia GeForce Experience was somehow forcing itself to be on top of the Assetto Window and causing massive slow downs. Disabled it and now all is good.
I was getting drops to 30fps with vsync on until i turned Anisotropic filter off in game and forced Anisotropic filter on in the Nvidia panel. Solid 60 fps most of the time now in cockpit view anyway.