Hello and welcome
I would advise that you re-do your installation before sending the board off for RMA.
Paying particular attention to your PSU connectors as it sounds like maybe, just maybe a connector was missed.
Can you provide a bit more information as to how you determined the board was DOA. I accept it would not post, but did the lights come on, did a fan spin up, where did the LED lights stick on? Stuff like that.
Cheers
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