Powers up with cpu unplugged but not when plugged

[bcortes657]

I have a fresh build that won’t power up. It’ll attempt to but shut down after a second. I’ve taken it apart and put it back but still no solution. I discovered it turns on when the cpu pwr is unplugged. Idk what to make of it because the psu powers up and the mb lights up when on and fans spin. It is only when the cpu is plugged into the mb that it shuts down.

What could be the issue? Bad mb or cpu? Maybe psu?

 

[Barty1884]

Potentially either/or, or something completely different.

What are you full system specs?