My viewable desktop has shrunk. My 17" apple multiple scan monitor looks like a 15" with a 3/4" black "frame around it. Besides the desk top getting smaller, my startup mac window, and the Eudora startup splash window, and the startup icons have all become about twice as big as before.In my monitor & sound control panel,I have only one resolution option- that is 640x480.(67hz). Somehow, the 1024x768 option is no longer there. I have tried rebuilding the desktop, zapping pram, deleting the monitors and sound prefs, and also the display prefs and finder prefs file. There was no change after re starting. Any ideas?