Asus suggested it is a DC voltage issue caused by either defective cables or defective Asus VE278Q monitors.
I respectfully disagree:
In my opinion it is not the cables for the following reasons.
All three cables or all three monitors must be bad because I was able to duplicate this issue with different variations of cables and monitors.
I also duplicated this issue connecting two displayport cables and one DVI cable and two DVI cables and one displayport cable.
Same reasoning for ASUS monitors – it is either the systemic flaw with all Asus VE278Qs or something else.
A workaround of powering of monitors during post does not work. ASUS monitors do not support hot plugging displayports. Doing so results in blank screen.
I am still hoping that Asus will still try to duplicate this in their lab…