My MBP (mid 2010) is suffering from the Intermittent black screen or loss of video issue. More specifically, it may happen that when switching from dedicated to integrated graphics, the screen goes black. Only a reboot helps in this case.
So I tried to disable the automatic graphics switching (via "System Preferences" -> "Energy Saver"). Nevertheless, graphics switching still occurs; I can't say when or what's causing that, though. It always appears to be the case after waking up from sleep / suspend-to-ram. As per gfxCardStatus, "Dynamic Switching" is enabled then, which is exactly what I seeked to prevent via the systems preferences.
Is there a way to permanently disable the dynamic graphics switching and only work with the discrete graphics? I wouldn't mind the shortened battery lifetime if that helped to prevent the black screen issue to occur.