Thanks KBT86
I've tried the compatibility mode amongst a myriad of other things that have been posted on various sites.
I've done a clean install of Win 7, then 8 and then 10. Loaded drivers, flashed the BIOS, tried different monitors, cables and adapters
None have detected the monitor hooked up to the DVI port.
This is obviously not a new or resolved issue as shown by this unanswered query from July of 2015:
I'm tossing in the towel on this one.
It irritates me when a company makes a product that has components that are usually easy to set up and then can't provide a working solution for setting up that product.
At least be honest and admit that it just doesn't work.