Videocard and its driver do not know about Windows screen modes. Windows manipulates its screen modes (and behavior of app windows). Of course Windows has to cooperate with videocard to maintain the list of monitors and their states. Maybe I should restrain myself from answering to you, since I am not helping by thinking academically. PS Are you sure it was only a videocard drivers that got updated? PPS I will repeat just in case: videocard does not know what it outputs to attached monitors, hence it can`t decide to switch screen modes, but Windows can - after it receives a notification about one of monitors turning on/off . That`s my understanding.