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I’m trying to to use the iMacs PSU to build a mini-itx hackintosh. Is it possible to use the power-on button in the iMac and then somehow connect it to the PSUs pin12, which should be the power-on signal? PSU pin-out: Power Supply (PSU) pin-out diagram I have removed the main board to make room for a display converter board to use the screen as a monitor, so I need to connect the power-on button directly to the PSU if possible.
Are you using the Apple power supply or the one that came with your conversion kit? You will need to emulate the circuit Apple uses on the logic board which feeds the Apple power supply the power on signal. Remember this is a soft power button, it is a momentary switch driving a signal line low (chassis ground).
