Very nice build Neilhart!
Nice to know you're a z270 Asrock fatality owner, this can help on know this little motherboard with TB functionality.
I chosen it for my
hack pro mkII because of the compact format.
Did you tested the Thunderbolt support?
I have a Apple TB display that works "intermittently": sometime boot ok, sometime black screen and I need reboot, unplug, and plug in first seconds to get monitor recognized.
Other z270 fatality users had same issue with other TB devices...
Also, there is a section or a moderator specialised on TB-video support?
Thanks