Hi folks - I use my MBP connected to an external display. From what I've noticed, the display on the MBP appears to be turned off when following the direction here: http://support.apple.com/kb/HT3131?viewlocale=en_US I've also noticed than I can effectively turn off the display on the MBP by toggling down brightness to it's minimum setting. My question is ... does toggling down brightness of the display really power down the display (cutting off the fluorescents on this mid 2007 model)? It seems to. Or is it simply attenuating the signal such that it appears to be off? I notice that when fully toggled down, the screen goes completely black and there is no discernible heat or light emanating from the display. The distinction between the two situations above involves heat dissipation during my encode sessions. Using a powerful, external fan, I can keep my CPU temperatures lower with the lid open. My goal here is to maximize the life of the laptop by actually keeping the display off to save energy and wear - since I prefer the external display, and keeping system temperatures as low as possible during full load. Any thoughts?