Re: Optiplex 755 only turns on through power supply button, no video output.
I think we've ruled it down to two components - either the motherboard itself or the PSU. Can I ask you to remove and reconnect all the power connections from the PSU to the motherboard? On some occasions, a loose connection can cause these problems.
I've also sent you a friend request so I can send you a private message - if you can add me as a friend and give me your service tag by private message, that would be a great help.
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