Sorry no idea. If it can't work in Windows, less hope it will work in Mac. What you mean "not recognized" in windows? an unknown device in device manager or nothing new at all? Are the antenna correctly connected?
1. change a high-quality HDMI cable ... (don't laugh, do introduce difference)
2. Found thinkpad x1c using eDP rather than LVDS, change HDMI patch
3. carefully follow the wonderful HDMI audio guide
now it seems ok..
almost everything is working perfectly except when i leave the system idle for enough time (say, 30m or more), there is 50% chance it cause a sudden reboot without closing running apps correctly .. and i have no clue how to track/debug it.
Native power management should be ok according to...
typically when i plug HDMI, internal display goes off, and no HDMI video at all. when unplug-HDMI, the LCD remain off.
Occasionally, there will be HDMI video+audio correctly, but internal LCD always off.
Never success when plug HDMI during boot up, both screen remain off.
thanks comment. Given currently this machine is my working machine, i didn't try further effort yet - means HDMI audio not work, Handoff not stable, trackpoint unstable...and fear to try High Sierra. :)
would like resume this debug progress shortly and report back here.
Without detail investigation, had thought those type-C should connect to TB3 controller, given they have display output capability in Windows - However, those ports also have USB capability, means TB3 control has its own USB implementation or somehow connect back to XHC?
So the question becomes...
Understand your suggestion. The @2 port didn’t connect to anything. Actually this laptop has 2 type-C TB and only one HDMI, no other display related port. Lenovo specs says it can connect to 3 displays at same time, means 2 TB+ 1 HDMI.
After HDMI was detected on @1, I should remove @2...