Dell Wyse 5070 won't start

This weekend my homelab took a big hit.

Not only did one ThinkCentre M720q Tiny stop booting whenever there is SODIMM RAM installed in slot 1 just playing a melody (used to work fine for a year), but today my Dell Wyse 5070 also decided to stop booting up (also was fine). When I plug in the power cord, an orange led flashes once and that's it.

Any chance this can by fixed? I tried different RAM sticks, no RAM, no SSD, removing the battery and placing the jumper on the bottommost position.