The outputs are taken when an external monitor is working and the laptop
display is off (no backlight and no image).

One more things. Not sure if it is related, but the automatic detection of
connecting the VGA monitor doesn't work either. With the previous laptop when I
connected an external display to the VGA port, the desktop environment (KDE or
GNOME) would automatically detect it and configure with the previous setup.
With this laptop it doesn't do it - I have to run the configuration utility
manually for it to see the new display.