I have two computers, a G4 dual 1.25 and a G5 dual 2Ghz. I have 50' VGA cables from both video outputs on each Mac going to 4 video projectors. I'm only able to have one video signal going out from each Mac. When I go to the displays preferences and click on "detect displays", the second projector goes yellowish for a couple of seconds and then goes away. With the G5, the other projector is fine when I do this. With the G4, both projectors disappear.
Could it be possible that there's not enough power to drive both VGA with 50' cables with a single video card? And if yes, are you aware of a VGA booster or do I have to put another video card to make it work? Note that I already have an AlchemyTV inside each computer for live video feed.