Hello ! I got a similar problem. I didn't find any solutions so I paid an IT to check my computer. He told me it was a manufacturing problem and couldn't do anything. He told me that I should send my laptop back and ask for a replacement. He told me it has something to do with my HDMI port, when I plug another monitor, it moves a little bit of my graphic card and it should be the problem. I'm gonna send it back this week, it's the second time it happens and I bought it one year ago...