It sounds like you are saying that the line is NOT present when running the U2515H standalone BID (Built-in Diagnostics) page 56? If true, then the U2515H is fine. We did provide a U2515H Windows 10 driver here, but I doubt that is the issue. The fault lies with either the operating system, video card, video card driver, or the cabling. You need to list the following =
* To what computer model is the monitor attached?
* What video card/GPU is in the computer?
* What video out ports are on the video card/GPU or computer?
* List all monitor cabling attached to the computer and the ports they are using

• What computer model is the monitor attached? ASUS GL552VX, 64-bit

• What video card/GPU is in the computer? GTX 950M 2GB GDDR5 Graphics

• What video out ports are on the video card/GPU or computer? Audio Ports - 1x Headphone-out & Audio-in Combo Jack, USB - 1 x USB 3.1 - 2 x USB 3.0 - 1 x USB 2.0, HDMI - 1 x HDMI, Video Port - None

• List all monitor cabling attached to the computer and the ports they are using – Only one HDMI and additional ShoX speaker attached to the monitor by USB

It sounds like you need to install the latest Nvidia GTX 950M driver for this ASUS ROG GL552VW 15.6″ Notebook. But you should join and post on the ASUS Gaming Notebook Forum to get assistance with it and other possible drivers.

Thanks Chris will do

Hi Chris I did install the latest Nvidia GTX 950M driver but still get the blue line, I checked this morning with a different laptop and still find the blue line, after that I checked again if the line is with the color screens and found that the blue line is on all the color screens

What is the way forward

Post pictures of the U2515H standalone BID (Built-in Diagnostics) page 56.

Thanks Chris the monitor is faulty and will be replaced