The power button on the case closes circuit when pressed, but the power supply doesn't turn on. The only things currently attached to or in the mobo are the CPU, the ATX connector (power connector) and the 4 wires which go to the power switch and power indicator light. There is no indication of anything when I press the power button. PS fan won't spin, lights don't turn on, nothing.
rolli, this is a Vista machine, a Pavilion slimline deal. Not too old, I would think.