This isn't too urgent of an issue, I've just been playing around with an older build today (actually a prebuilt Compaq Presario PC ) and this occurrence has piqued my curiosity more than anything. When I get all the essentials plugged in to power up and try to short the "power on" pins using a screwdriver (or any other type of metal component), the motherboard doesn't even recognize it and nothing happens. If I just plug in the header for the front case buttons, the power button will power on everything, CPU fan gets to spinning and everything is okay. Why does the motherboard require the power button? Why wouldn't shorting the pins work? (And yes, I KNOW I was attempting the procedure on the correct pins, I've ruled this out anyways with extensive trial and error). Is it the ancient power supply that came with PC?