hdmi monitor specification

Question

some hdmi monitors i use, some don't. what makes the difference?
working: benq
not working: iiyama prolite b2409hds
is it possible to make (older?) monitors work as well?

anonymous · Answer

Usually, it is the HDMI monitor that did not supply EDID information that is causing the issue.
Less likely is monitor's HDCP support.
None of these would be a problem for modern HDMI monitors.