I have a Princeton Ultra 72 with some sort of energy saving function that doesnt power up until you plug the chord into something. Like if its not plugged into anything it shows a green light and displays 'no signal'. But if it is plugged into a computer (even if the computer is off) it will show a yellow light and go black. When I plug it into my 12" powerbook all I get is the 'no signal' screen. It doesnt seem that my monitor recognizes the powerbook, even though the Ultra 72 shows up in the powerbook's options and stuff... 😕