Hi to @ll
I have a Pentium I5, 8 Gb RAM with a AMD Radeon HD 7400 Series graphic adapter.
When I connect my second display to the dvi port, the graphic card do not recognize the device, and I have a warning message on the display: "Check signal cable".
I have changed the cable already
When I disconnect my primary display (that is connected to the VGA port) and connect the second display to the VGA port, the display works properly.
Boris - UIO - EC