I was surprised one day to find an inch of white line running from top to bottom on my screen. Then after a week it expanded to two inches white line, then suddenly it turned all black and I can't see two inches of my screen from the right edge. I was reading some forums and found out that I can use a dell monitor as a secondary monitor, but is it possible to use the dell monitor as the primary monitor in case the black line will spread throughout the entire iMac screen? so the iMac would serve as a stand alone processor like a regular desktop? mahalo!!!