anyway, if the psu works with the paperclip, its not likely the PSU being faulty.

1) Did you make sure to plug in the 20+4 pin to the motherboard AND the 4 pin cpu connector?
2) if above is right, are you trying to turn on via the power button? if so have you connected the headers to the motherboard? and are you sure the headers are set up right?

If both above are you SURE are right, then it may be a faulty motherboard.

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