I have a 13" Macbook (late 2008) connected to an external monitor using a mini-displayport to dvi adapter. I usually have it on extended mode, with the external monitor set as primary. AC adapter is plugged in all the time. I usually close the lid on the macbook when I am not using it, so that it will go into sleep mode. When I open the lid again, it wakes up, and the external monitor is detected normally. Every application window is where I left it. However, I upgraded to Snow Leopard (10.6.1) recently and I encountered a problem. Whenever I open the lid to wake up, as I described above, the external monitor is not detected at all. I have tried to plug/unplug the dvi adapter, turn on/off the external monitor, but it is still not detected. The only way to detect the external monitor is to go to System Preferences->Display then click on 'Detect Displays'. This is a major hassle, because I also have to move the application windows around from the macbook display back to the external monitor. Anyone else have the same issue?