Just received my replacement NUC DN2820FYKH after the original had thermal trip warning and I'm having some problems getting it set back up.
I had to revert the BIOS back to 21 so I could install openelec from USB all installed fine but now I am unable to upgrade the Bios, when it reboots to perform the upgrade there is no display on the TV as if the hdmi isn't connected. same happens if I power the box off and back on with remote it won't give a display again without being unplugged.
Tried removing the SSD with openelec on it to see if that was the problem but still unable to upgrade the bios.