(
Ubuntu - 18.04.3
Kernel: x86_64 Linux 5.3.0-26-generic
GPU: GeForce GTX 1660 Ti
Nvidia driver 435 (проприетарный).
)
I bought a Legion Y740 laptop. Initially, I installed it on Ubuntu, and it worked for me to connect to external monitors (at least through thynderbolt the image was displayed Hdmi did not check at that time). Then I decided to install dualbut from windows10 and ubuntu.
But after all this, after a new installation of Ubuntu with Windows, the system stopped detecting external monitors. (Windows sees everything correctly. So the options to change cables, check video slots or exclude the use of adapters do not immediately fit).
I tried different versions of the proprietary and open source drivers of nvidia (I changed them through Software & update in the Additional drivers tab). I also tried the default Nouveau driver for X, but the result is the same.
I was more confused by the conclusion:
xrandr
Screen 0: minimum 8 x 8, current 1920 x 1080, maximum 32767 x 32767
eDP-1-1 connected primary 1920x1080+0+0 (normal left inverted right x axis y axis) 344mm x 193mm
1920x1080 144.00*+
in theory, there should be information about at least (thynderbold, Mini-DP, hdmi ports).
In the BIOS there is an option - Adaptive option (the choice is either discrete or adaptive option). I tried to turn it on - only discrete graphics, but in this case even a resolution image was displayed on the laptop screen (obviously less than 800x600. It may be somewhere in 400 units in width). (By the way, the resolution in Grub also dropped to the same values. Windows also works fine).
and Wayland session:
Screen 0: minimum 320 x 200, current 7040 x 1440, maximum 8192 x 8192
XWAYLAND0 connected 1920x1080+0+0 (normal left inverted right x axis y axis) 340mm x 190mm
1920x1080 143.88*+
XWAYLAND1 connected 2560x1440+4480+0 (normal left inverted right x axis y axis) 530mm x 300mm
2560x1440 59.91*+
XWAYLAND3 connected 2560x1440+1920+0 (normal left inverted right x axis y axis) 530mm x 300mm
2560x1440 59.91*+
since two cables (thunderbold and hdmi) went straight from one monitor to a laptop, they got two at once. If you move the mouse to the right, then it goes beyond the edge, into the area of another monitor. But the image itself is not displayed on the monitor. p.s. Yes, I chose the desired video output in the monitor settings, from which I expected to see the result.
