Sorry if this has been addressed before, but the search engine here is dumb and google was failing me too.

I'm trying to set up Steam Link on my Android devices.

In spite of a warning popup that it is untested, my Samsung Tablet (Galaxy A from two years ago), the network test comes back with good up to 100 Mbps (WiFi), with 4K as an option.

But my Hisense 4K TV (last year's model), the network check says good up to 95 Mbps (Ethernet), and no compatibility warning, but it's only listing default and 1080p.

The Windows 10 PC supports 4K graphics, drivers are current. ("It's an older nVidia card, sir. But, it checks out.") Games play fine at that resolution.

I've poked around in the settings to find where the resource caps are, and tried setting the TV to 4k instead of Automatic (1920x1080) but that setting doesn't stick when I close the settings. I go back in, and sure enough it's on automatic again.

What else might be going on here?