Or - maybe simpler : Does this board support BOTH HDMI and DVI simultaneously or just one of them ? If it does not , that explains it . The documentation available from intel does not say that explicitly.
OK issue resolved
The board can support both DVI and HDMI but not when another graphics card is enabled. When using another graphics card + the onboard one must set the bios to "IGD always on" and even then the other card operates only with the DVI and not the HDMI
So the solution found was to get another graphics card that has a PCI Express X 1 interface and add it to the computer
I got a PNY NVS 300 PCIeX1 card that supports two extra monitors. So now the computer is working fine with 5 monitors and I still have yet another PCIeX1 slot if more needed.
Hope that is helpful for someone