My Raspberry Pi 4 was working fine but as I was using it on a
3840x1440 screen I decided to set that resolution for the raspberry as well. However, very quickly after it went totally black and my screen turned off.
Rebooting the Raspberry Pi shows the desktop for around 15 sec. I tried to set the resolution back to full Hd but wasn't able to do so within the given timing. I also tried to force resolution via the config file.
hotplug is activated as well as HDMI boost, besides that all the HDMI config settings are commented out.