PINE64

I've tried the default KDE, Diet Pi, Armbian, and Manjaro LXQT and have not managed to get HDMI output. I'm able to detect that an HDMI monitor is connected but can not seem to get it to actually display. Any advice hugely appreciated!

Go back to Manjaro LXQT. I was able to get it working if I dropped the resolution (of the external monitor) to 1600x1200. Of course there were other problems with Manjaro, like I am not sure it is really sleeping (since the power light stays on).