Low whine from power supply(no fans spinning), no power to motherboard.

[chromapagou]

Firstly, im going to apologize for the mini essay of text. Kind of new to building but I've purchased a new power supply(Coolmaster Masterwatt 500), motherboard(Asrock AB350M Pro4), and processor (AMD Ryzen 5 1400). When i got home i put in the processor and fan, plugged up the power supply and switched it on, only to get no reaction at all. I've tried two psu (an old dying one i had, and new one purchased) both only gave me a whine, with no response from the board. Yet both supplies powered up an old Intel board i had...so mostly wondering what might be some issues, or some suggestions on fixing. I don't want to assume its a bad board as ive gotten it replaced twice (one of which was actually a bad board)..

 

[rocktalkrock]

Could there be an extra standoff in the case shorting out the motherboard?

 

[chromapagou]

Could there be an extra standoff in the case shorting out the motherboard?

I haven't even placed it in the case yet, and thats whats confusing me hmm