HDMI Expansion not working (Win11)

I’ve tried 2 cables, 2 monitors. No luck. I can connect a monitor using my Lenovo usbc dock and it works fine but I can’t seem to connect to anything using the hdmi expansion card.

What cables and monitors, specifically? Which ports on the monitors? HDMI can be a deceptively complex video interface, and there are a variety of ways that this can go wrong.

When you do plug in the monitors, does anything happen on either the computer or monitor? “Not working” can mean a lot of things, you see.