The test pattern does not appear on the monitor.
The monitor does work with HDMI output from an NES Classic and Raspberry Pi, using the same DVI/HDMI cable.
I didn’t know there was a special DVI mode. Looking at the wiki, do you mean the “TX output” option? If so, is that only accessible with the menu (orange) buttons on the remote, or is there a shortcut? I’ll try it later tonight.