A Macintosh II with multiple video cards can have multiple monitors displaying
different data, arranged in such a way that each display could be updated
independently.
Since each card is mapped into memory independently of any other video card,
this would not be true multiprocessing, simply an extended video screen
dispersed over several monitors.
A Macintosh program can update any window on a screen it chooses (in this case,
it would be a very large screen).
Writing directly to a video card in a slot is not suggested; however, any
window that is moved from the "system screen" will continue to be active upon
monitors connected to additional video cards.
Multiple screens can be located in adjacent positions, including corner to
corner. The logical positioning of the screen can be adjusted through the
control panel monitor icon. Operations performed on a window will be
appropriately displayed in the screen containing that window.
For example, If 6 documents were opened, and each document dragged
to a separate screen (all screens being adjacent or corner to corner), text
could then be typed into any document on any of the screens merely by moving
the cursor to the desired screen and window.
Each portion of this large screen composed of the multiple video cards is
stored separately; any operations on windows by the Macintosh II or user can
occur, regardless of the cursor location.
(NOTE: The screen updates will be somewhat slowed by the increased traffic on
NuBus.)