Chosen Solution
I have an XPS 15 9560 4k display and the lower part has messed up horizontal lines. the upper 3/4 of the screen is fine, the lower 1/4 is the only issue.
Hi @buenabee, Have you tried switching the between the integrated onboard GPU (Intel) and the discrete Nvidia GPU controller just to make sure that it isn’t a problem with the controller? If it happens with both GPUs, try connecting an external monitor to the laptop just to make sure that it isn’t a problem with the motherboard. Even a TV can be used as an external monitor as long as it has a HDMI input and you have a compatible HDMI cable to connect the laptop and the TV together. If it doesn’t happen on the external monitor, then you may either have a loose display cable connection on the motherboard, a faulty display cable or a faulty LCD panel. Here’s a link to the service manual for the laptop, taken from this webpage. Scroll to p.74 to view the necessary pre-requisite steps and then the procedure to remove the display panel. This will allow you to inspect the display cable connection and if it appears to be OK, then determine whether it is a faulty cable or panel.
