The green looks great in that picture?
* To what computer model, video card, operating system are you connecting the U2718Q?
* You should be using the supplied Mini-DP to DP cable that shipped in the U2718Q box
* Open the U2718Q User's Guide to page 51
* Follow the instructions to run the U2718Q BID (Built-in Diagnostics)
* Post a picture of the BID green screen
From a warranty perspective, the BID green screen passes. We cannot exchange this monitor. You have two options =
* Purchase 3rd party color calibration hardware (colorimeter) and software and calibrate the monitor
* Return the monitor for refund
Can't return because with HDMI work fine, and they say, monitor ok, this problem only with any DP or mDP cable! And this "bad pixel test" not professional for professional display!