Power the controller, no need for hashboards.
This is a serial link, old fashioned method you may not be familiar with depending on your age, so use a serial terminal, not ssh client; forget putty.
If you do it correctly you should get a prompt when you plug the cable and hit enter; probably login and password.
It works either through putty or cooltherm, problem i had was when prompted for login, i couldnt type anything, tho led light was blinking on controller when i tried.