I'm struggling! I have a 2006 Mac Mini running Lion connected to a 20" Cinema Display. I want to be able to press the power button on the display to sleep the system with just that action. Currently, when I press the power button one the display, I get this screen: I have System Preferences -> Display -> Options set to "Pressing the display's power button puts the computer to sleep or wakes it". I have Energy saver set to check "Allow power button to put the computer to sleep". If I press and hold the power button on the display, nothing happens at all. If I set "Pressing the display's power button turns the display on and off", it works as expected and doesn't give me the dialog box. What is wrong here? I want to do this since I'm running the mini without a keyboard or mouse to power a slideshow on the 20" ACD. I'd like to be able to tap the monitor power button to wake the mini, let the slideshow go on (screensaver) and tap the power button to sleep it again at night.