For a while, using DisplayPort (and maybe HDMI, too) I have been experiencing periodic moments when the screen goes black, and then after a few seconds recovers.
Occasionally this will happen and the machine will crash and completely reboot.
This is running Ubuntu Linux Xen. See attached output of ssu program for details.
The log file is spewing stuff like this. Note the times! It's streaming dozens per second, mostly the Fault errors.
Dec 17 15:40:51 tesseract kernel: [ 5292.968233] [drm:gen8_irq_handler [i915]] *ERROR* Fault errors on pipe A: 0x00000080
Dec 17 15:40:51 tesseract kernel: [ 5292.984683] [drm:gen8_irq_handler [i915]] *ERROR* Fault errors on pipe A: 0x00000080
Dec 17 15:40:51 tesseract kernel: [ 5292.984774] [drm:gen8_irq_handler [i915]] *ERROR* Fault errors on pipe A: 0x00000080
Dec 17 15:40:51 tesseract gnome-shell[1890]: [AppIndicatorSupport-WARN] Attempting to re-register :1.68/org/ayatana/NotificationItem/multiload; resetting instead
Dec 17 15:40:51 tesseract gnome-shell[1890]: [AppIndicatorSupport-WARN] Item :1.68/org/ayatana/NotificationItem/multiload is already registered
Dec 17 15:40:51 tesseract gnome-shell[1890]: [AppIndicatorSupport-WARN] Attempting to re-register :1.68/org/ayatana/NotificationItem/multiload; resetting instead
Dec 17 15:40:51 tesseract gnome-shell[1890]: [AppIndicatorSupport-WARN] Item :1.68/org/ayatana/NotificationItem/multiload is already registered
Dec 17 15:40:51 tesseract kernel: [ 5293.001263] [drm:gen8_irq_handler [i915]] *ERROR* Fault errors on pipe A: 0x00000080
Dec 17 15:40:51 tesseract kernel: [ 5293.001289] [drm:gen8_irq_handler [i915]] *ERROR* Fault errors on pipe A: 0x00000080
Dec 17 15:40:51 tesseract kernel: [ 5293.018145] [drm:gen8_irq_handler [i915]] *ERROR* Fault errors on pipe A: 0x00000080
Dec 17 15:40:51 tesseract kernel: [ 5293.018221] [drm:gen8_irq_handler [i915]] *ERROR* Fault errors on pipe A: 0x00000080
Dec 17 15:40:51 tesseract kernel: [ 5293.034182] [drm:gen8_irq_handler [i915]] *ERROR* Fault errors on pipe A: 0x00000080
Dec 17 15:40:51 tesseract kernel: [ 5293.034198] [drm:gen8_irq_handler [i915]] *ERROR* Fault errors on pipe A: 0x00000080
...
The other thing which may or may not be related, is that the sound via display port is garbled and virtually unintelligible.
The monitor is a Samsung C27F591FDU, which has built-in speakers. I was able to listen to sound via the headphone jack on the NUC previously.
I think that was using the HDMI connection, or maybe when using a USB-C to HDMI adapter. It would be nice to get this fixed.
I think there must be some problem with the DisplayPort drivers.
Any help very much appreciated.