Part 1 of a video tutorial on power supplies for beginners explaining how you can easily get set up to test, modify and use power supplies ... ATX Power Supply Tutorial. Pin: Name: Colour: Description: 1: 3.3V : Orange +3.3 VDC: 2: 3.3V : Orange +3.3 VDC: 3: ... this supply are the orange wires. The wht wire is the ''PS On''. Compaq is …