Question PC will only spin up without CPU power connected

ap3

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Jun 14, 2020
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Hello! new build PC with specs as follows:

CPU: i5-9600k
Mobo: MSI z390 gaming edge ac
GPU: rtx 2070 super
Psu: seasonic pulse gm650
RAM: 16gb (8x2) T series

If the CPU power is connected ev erything will spin up for 1/10th of a second then stop. without the CPU power all the fans/gpu will spin up and the MOBO will indicate it is detecting the RAM sticks in the correct places. Is the motherboard likely the issue? I have another motherboard on the way to replace this one but was hoping there is some fix that I am missing.

Thank you!