Barco Coronis 3MP Installation & User Manual page 79

If you are using a Quad-Head Configuration repeat all of the
above steps for the two displays on the second display
controller.
Note: If you have a single display configuration and you
have enabled DualView, Windows will not allow you to
attach the second head. This is normal and not a bug.
After enablingDualView and setting the resolutions in a
Quad-Head Configuration you may need to drag the heads
into the proper position in the window on the "Settings" tab,
so that the arrangement in the window on the "Settings" tab
matches the physical arrangement of your configuration.
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