Mac Mini still thinks external display is connected even when powered off... Why?

[Chase R]

Okay so here's my setup: I have a 2009 Mac Mini connected to a 22" LG monitor via Mini-DVI port and it's also connected to a 50" Pioneer Plasma (in the next room) via Mini-Displayport. Everything works perfect except that when I turn off the Pioneer Plasma, my mouse can still scroll over from the LG monitor to the Plasma. I've also noticed that my screensaver is laggy even when the Plasma is turned off (usually that happens when it's drawing the screensaver on both screens) so it must still be sending a video signal out of the Mini Displayport.

Anyone experience this problem? Why does it do this?

 

[DannySmurf]

Is the behaviour the same if you unplug the monitor instead of powering it off? If yes, then the OS is not switching the display; if no, the monitor is probably in low-power mode, not actually off.

 

[Chase R]

Is the behaviour the same if you unplug the monitor instead of powering it off? If yes, then the OS is not switching the display; if no, the monitor is probably in low-power mode, not actually off.

When I unplug the TV (Mini Displayport), it works like it should, the OS switches to just using my LG monitor. So you were right, my TV does go into "low-power" mode or something like that instead of actually turning completely off. There is a button to turn it completely off but I was told that wasn't recommended.

Any ideas on what I can do to make it work like it should without actually completely powering off my TV?

 

[DannySmurf]

Not really. Why isn't that "recommended?"