RE: Flickering horizontal lines always on screen (XPS 15 9530)
I've got an M3800 which is an identical build to the XPS15. I had my screen replaced in May due to some dead pixels appearing - after a week I started seeing the problem with the screen flickering.
My suspicion is that a faulty or refurbished screen was used under warranty as a replacement screen. Needless to say, I've run all the tests (and them some more) above..
What I have noticed, is the vertical lines
- are always formed from the same colour as the very bottom row of pixels on my laptop screen, and
- they can change depending on the colour of the rows
- the vertical lines or blacked out screen can also happen when the computer is starting up (i.e. on the boot screen)
- if it happens on the Windows10 login screen the lines will be a different colour (the colour of the bottom row of pixels of the login screen), then they will change to the colour of the taskbar
- it's the same patch of screen affected, about 5/6th of the screen has the lines or goes black, the remaining 1/6th to the far right either shows the rest of the screen or goes white/black
Above: The external monitor is a duplicate of the laptop monitor. The light grey lines on the laptop screen are from the open applications (as can be seen in the taskbar on the duplicated monitor - chrome (offscreen), spotify, outlook, google keep, citrix). The lighter mid-grey area to the very left of the laptop screen is created from the Cortana "Ask me anything" field in the taskbar.
Above: Only one application open this time (chrome), therefore only one light grey verticle line. Each shade of grey corresponds to the colour of the bottom-most row of the screen (the taskbar in my case).
Tests I've done...
1. Safe mode: flickering lines still present. Changing the resolution from low to native in safe mode seems to make the flickering problem more apparent.
2. External monitor: no flickering lines on the monitor at all, only seen on laptop screen
3. LCD BIST - solid colours ok (although catching the flickering problem at the same time as the BIST test is difficult to do as the flickering happens a lot, randomly (and often makes my screen solid black/white after a while)
4. Diagnostics - through the Dell website, nothing found
5. Driver update - checked all drivers and rolled forwards to the latest, backwards to the most stable, doesn't make a difference.