I have Ubuntu 20.04 installed on an Intel NUC (NUC7i7BNK). The NUC has an Intel Iris Plus 650 GPU (and no NVIDIA cards inside). The monitor I am using is DELL P2311H. The monitor does not support HDMI input, so I am using an HDMI to DVI adapter. The first weird thing is that when I plug the HDMI interface into the NUC, the monitor cannot detect any signal from the machine (showing No DVI-D cable instead of No Signal). I have to use another HDMI-Thunderbolt adapter and use the Thunderbolt interface on the NUC to get the display.
The second weird thing is that when I boot into Ubuntu, sometimes I get No Signal on my monitor when it reaches the login screen or after I have entered my password (and hit Enter). I can disconnect the monitor and reconnect to get the display again, but doing that almost every time I boot the system is quite annoying.
The third weird thing is that when I open the Settings app in Ubuntu, I get No Signal on the monitor most of the time. This issue cannot be solved by the disconnect-reconnect method. The only thing I could do is to reboot.
The fourth weird thing is that I get No Signal into BIOS or the NUC power button menu.
I do not think the cables have any problem. When I boot into another OS (Windows 10) in the machine, the display output is stable. Also when I connect the monitor using the same method to my Macbook Air, the display output is also perfectly stable.
These video output issues are really annoying and are obstacles to my development. I was wondering if anyone here has any idea to fix these issues. Thank you!
