The software uses OpenGL for the user interface display. OpenGL refreshes the screen based on the driver settings. While various driver features may affect the refresh rate of the screen, one of the most common reasons is the activation of the V-Sync (vertical sync). If the V-Sync is set on, then the user interface won't refresh faster than the maximum refresh rate of the screen mode in use (usually 60Hz, i.e. 60 fps).

Disabling the V-Sync can solve the problem. Please consult the section on the GPU configuration.