Thanks for the note. I have a new display port to hdmi adapter, but it's possible that's not working. But I suspect it is a driver issue. My monitor is a 3 yr old Samsung, and I don't know if it's plug&splay with the default settings in this new workstation.
Newer Monitors show plug&play as a feature, and one Hp monitor adds: "one cable setup with DP-DP cable". Will I needa newer monitor, or at least borrow one that's plug&Play ?