LG 26TS30MF Installation Manual page 37

 DP Cable
In case of 55LV77A, 55LV75A
DP Cable
NOTE
 If the signal is stable and there is no cable loss, in general, up to 25 Monitors can be connected
via the DP Out port (at the recommended resolution).
If you want to connect more than this number of monitor, it is recommended to us a distributor.
 When the Tile Mode is configured via DP, max. 8 monitors can play HDCP-encrypted content.
 If the signal cable between the product and your PC is too long, make sure to use the Booster
or optical cable
 If input signals are received through the DVI/HDMI cable, multiple monitors cannot be connected
via the DP Out port.
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