XPS 13-9350, DA200, USB-C to HDMI, cannot change WiFi power output

Hi, All,

I have an XPS 13-9350, and a DA200 adapter for the USB-C port. The inability to connect to HDMI through this configuration is well-documented everywhere from Dell Community pages and independent hardware forums to irate 1-star reviews on retail sites. It seems that, up through last year, the best solution was to go to Device Manager -> Network Adapters -> WiFi Card -> Advanced -> Power and change the WiFi output strength to 75%. The theory was that the USB-C and WiFi card were drawing from the same power source, and that the latter was always drawing so much that it interfered with the function of the USB-C port.

Well. I tried to do this today, and it looks like "Power" has disappeared from the menu in the advanced settings for the WiFi card (image below shows the menu in question superimposed over a site that gives this advice).

As I verified recently, my laptop still can't connect to HDMI through the DA200 adapter (though VGA and everything else on the adapter does work).

Someone please help!