Notebook wih external screen via hdmi problem

[skibby]

Hello community,
i try to connect an external screen to my HP Elitebook 840 G8 via hdmi.

it boots until the emulationstation bootscreen is shown then the external screen goes black and turn off.

i already tried the instructions from the wiki "Configure an external screen"

i opened the recalbox log, as described, and found that lines:
Connected screen(s) / Max resolution / Fallback resolution lower than FullHD:
eDP1;1920x1080;1920x1080
Force selected output eDP1, disable others
xrandr --output eDP1 --auto

So i changed the values in recalbox.conf to:

But still the same prob, boot until emulationstation bootscreen then it goes black.

the external screen is a screen within an arcade1up cabinet.
before i had an raspi4 with recalbox connected and that worked without any probs.

could anyone please help?

[skibby]

i already found the solution.
the value eDP1 was for the internal display from the notebook. i had to use HDMI1 instead.
now everything works fine.