9 How to assemble your monitor hardware
Then tilt the monitor.
To avoid the edge of the LCD display hitting the
monitor base surface while it is being rotated, do tilt
and extend the monitor to the highest position before
you start to rotate the display.
Rotate the monitor 90 degrees counter-clockwise (from
the rear side) as illustrated.
To use the monitor in a vertical (portrait) orientation, see
Rotating the monitor (optional) on page 13 for more
information.