I don ' t have my graphics card yet so of now there is no HDMI port <| sep |> The cable is just 3 connector spots whatever they are called Terminals ? Positions ? . Use one for power , one for data , the last for ground . You could run vanilla USB 2 over 3 . 5 mm jacks with the 4 position ones smartphones use . The issue is with passive connectors that always supply power , as you slide the pin in , it touches them all in sequence so you would get power supplied down the data lines , which might damage the device on the other end . This is why USB has all the pins in a row . You can make a hardware delay , like apple ' s MagSafe waits 1 second after it learns of a connection to supply full voltage . The cheap dangerous knockoff chargers don ' t wait so they spark when you plug them in . The same could happen I think to something wanting a lot of power , like a hard disk . I assume this issue prevented the pinstyle connectors from being used in the past , and the more modern connectors are smaller , have more positions , less depth in the unit so less leverage and the pins can easily have the tips snap off under stress . Apple used to use a 3 . 5 mm jack with a metal ring around it for Chargers the old ones before MagSafe and those pins snapped off the ground tip inside the Macs all the time . I had to repair hundreds of units with damaged power connectors , so maybe they aren ' t the best connector .