04-23-2019 11:37 AM - edited 04-23-2019 02:37 PM
This morning I found myself clenching the rear for all that is dear to me when my Thinkpad X1 Carbon 6th Gen's Full HD Touchscreen started to misbehave. In this thread I will describe the symptoms and finally the resolvement, as well as log anymore occurences of the behaviour it showed today.
After recovering from sleep on my Linux installation, I had to go back to real work and reboot to my Windows 10 Home partition. During the whole recovery, reboot and log-in process, no abnormalities where observed. A few moments after logging in however (it can't have been more than 20 seconds), my display showed an image like this: (recreation made in photoshop)
I was shocked to the core, however immediately assumed it must have been some kind of Windows 10 problem, and rebooted the system swiftly.
The computer did not power off immediately, but merely showed a black screen after Windows said it was "Restarting", and blew its fan to pretend it was actually very busy. After two minutes I forcefully shut it down and waited a couple of seconds before turning it back on.
The BIOS screen showed no abnormalities, but as soon as the spinning circles were done chasing eachother, I was objectively horrified by what my lock-screen, and subsequent desktop looked like. Here is a GIF that simulates what I saw: (best viewed on a 60Hz Monitor)
It was quite the shock!
To be clear, this isn't software or video output causing the issue. Investigation resulted in concluding that the backlight was doing this crazy thing, since I couldn't see the blacks getting any lighter, and neither did the whites get any lighter. It was fairly similar to the flickering you see when you video a monitor that is not quite in sync with the framerate of your camera, except it was the whole screen flickering like this.
After rebooting a few more times and also trying the linux partition again to see if it was a Windows issue, the problem persisted as far as the BIOS Setup menu, where the flickering also occured. I was panicking and not getting any work done, so decided to just use the second monitor for the time being.
After working for a few minutes on my second monitor, I just had to check again if my built-in display had stopped its very worrisome flickering. And while it wasn't completely gone, it had, to my surprise, gotten about half as intense as it was when it first started.
I decided to turn the screen off once more and check back in a few moments, and in the course of an hour or three, the flickering lessened to an extent that I'm now, at the end of my workday, typing this on the train home with a perfectly fine and stable screen, as if nothing had ever happened.
I would like to find out the cause of this issue, and therefore I am recording here any instance of it ever occuring again, and I would like others with the same problem to join and describe their actions leading up to the problem if they ever experience the same thing. Furthermore I hope Lenovo could shine a (preferably non-flickering) light on what might be the root of the behaviour I have seen today.