Thank you for your respond.
There is a BIOS, but I there is no on-board video option. Male VGA and Printer (pink) port. I only have recent GPU. So I have to go overkill on this one...
For the Relay, I never used one.
I have to connect "Signal" to any digital output of my arduino, "Ground" to ground. "5V Vcc" to the power Switch (6 or 8?).
Do I have to use "NC", "C" and "NO" from the relay?