Running Two Types Voltages on Due 12V and 5V

Thank you for the reply, so does that mean if I connect the 5V DC-DC onto the 5V pin on the Arduino Due it should power up the DUE and the attached devices as well, and so the 12V to the Due Jack is not needed?

Also, if it is powered in that way and the Due needs to be connected to a PC to communicate it should be fine right or would there be other issues?

Best regards

Mo