Pipeline, thanks
funny that you mentioned that. After trying many things, I uninstalled motherboard driver (deleted files too) and tried just base, Win 10 Microsoft driver. Did not help. After spending many hours on this, I am starting to get a feeling it is a software and not hardware bug. Those thunderbolt 3 ports are very tricky tings, because of many factors, including security bios features on the port itself and how it routes features, in my case power+Display port in one shot. I am suspecting Nvidia driver is not catching up to "accept" monitor through thunderbolt. I found not very "intelligent" workaround by enabling/ disabling video driver while monitor is plugged. Seems to do the trick. Have 3 weeks to think about it before sending it for MB replacement. Hopefully they come out with driver patch.

P.S. Still want to know if somebody has same Thunderbolt software and if it shows a hard drive for example in that tray when it is plugged.

I tried tech support, they rather replace motherboard than spend 10 minutes of level 2 troubleshooting. Such a waste of resources and time...