Why can't ubuntu see the D-SUB port?

Question

linux

I bought a new monitor, which I connect directly to the video card (DP).
I connect the second (old) monitor to the motherboard (D-SUB).
In BIOS, I turn on the integrated graphics mode, which allows both the video card and the integrated board to work.
If you define the video card by default, then ubuntu does not see the ports of the motherboard.

xrandr
Screen 0: minimum 8 x 8, current 3840 x 2160, maximum 32767 x 32767
DP-0 disconnected (normal left inverted right x axis y axis)
DP-1 disconnected (normal left inverted right x axis y axis)
DP-2 disconnected (normal left inverted right x axis y axis)
DP-3 disconnected (normal left inverted right x axis y axis)
HDMI-0 disconnected (normal left inverted right x axis y axis)
DP-4 connected primary 3840x2160+0+0 (normal left inverted right x axis y axis) 600mm x 340mm
   3840x2160     60.00*+  30.00  
   2560x1440     59.95  
   1920x1080     60.00    59.94  
   1600x900      60.00  
   1280x1024     60.02  
   1280x800      59.81  
   1280x720      60.00    59.94  
   1152x864      59.96  
   1024x768      60.00  
   800x600       60.32  
   720x480       59.94  
   640x480       59.94    59.93  
DP-5 disconnected (normal left inverted right x axis y axis)

If you set the default motherboard, then ubuntu does not start.
Before loading the logging window

After trying to log

in What could be the problem? Previously, the second monitor (D-SUB) did not connect. If you connect it and make a basic adapter - the motherboard the result is the same