Hi, I just connected my 42" Plasma display to my Mac Pro to be able to run movies, play games etc. on it (BF2 is really nice on a 42" screen However OSX and Windows don't share the same idea of what DVI port should be the primary port. OSX wants the port that is closest to the other ports (below). While windows (in a dual setup) want's the other port to be the primary. That's normally not a problem since you can change that in windows. Now.. In the ATI drivers and the windows display pref. that button that says "use this display as primary". or something is GRAYED out.. Anyone else with the same experience or any tips ?