In an ATX case there are two wires coming from the power button that connect to the motherboard via a connector that looks similar to a jumper. The power button on the front of the case is a momentary-on pushbutton, just like an arcade button. In fact, if you took a small piece of wire and touched the two metal posts this jumper-connector touches, you would turn on the computer. This is one of the easiest things you can do, and gives the cabinet a "finished" feel, rather than having to fish around and find the PC power button. Don't be scared to cut the wires - you can always twist them back together and tape them off! It's almost impossible to screw anything up trying this...