FPS

To maximize your FPS to the fullest, you need to disable some things which may affect your gameplay. A big one is r_shadows from 1 to 0, in console type in r_shadows 0. There are a few other things you can type in too, like fps_max 0, r_3dsky 0, r_cheapwaterstart 1, r_decals 1, and more. Of course there are also addons out there that will do this for you every time you get into single player.