HP E27m 27" 16:9 IPS Monitor with USB Type-C Docking - Manual (Page 33)

3. Add a second monitor by connecting a DisplayPort cable between the DisplayPort OUT port on the
primary monitor and the DisplayPort IN port on a secondary monitor.
NOTE: One of the two daisy-chained monitors needs to have DisplayPort IN and OUT video ports. The
last monitor in the chain needs only a DisplayPort IN video port.
4. Set a connected monitor to display the same image as the primary monitor or a different image.
If the DisplayPort Mode setting is DisplayPort 1.1, the setting automatically changes to DisplayPort 1.2
when DisplayPort OUT is connected to the secondary monitor.
5. To connect additional monitors (up to four maximum), press the Menu button to open the OSD menu.
Navigate to the USB Type-C configuration and select USB-C Video+USB2.0 .
NOTE: All but the final monitor in the chain must support DisplayPort multistreaming.
6. Connect the DisplayPort cable from the DisplayPort OUT port of one monitor to the DisplayPort IN port of
the next monitor.
DisplayPort multistreaming (select models) 27