that would be the in-game setting for enabling/disabling v-sync.in practice, vsync will cap your fps to whatever the refresh rate of your monitor is, and this can cause the game to look very smooth, but react strangely depending on the number of frames per second you're using and how it is meshing with the server's cycles.in r1q2, with vsync on (gl_swapinterval 1) your maxfps will also be your packets per second rate to/from the server.