AB350 Gaming K4 -almost nothing

Brief outline- so maybe 15 heard ago, I built several pcs for myself. I was never super knowledgeable, but was able to figure things out and didn't have much trouble. Fast forward today - I agreed to build my stepson a gaming PC
Ryzen 2700x
ASRock AB350 Gaming 4k
16 gig Corsair vengance DDR 4 3000Mhz RAM
LSP Ultra 650 PSU ( this is the only used part in the build)
MSI 580 8GB GPu
And a Corsair Carbide Case

Things went together pretty seemlessly until I Peter it up.   As soon as I put it in, the red LED under the board chipset heat sink lights up, the RGB keyboard lights up, but that's it.   No lights on the power switch, nothing... No post either.

I took the GPU and ran back out changed the DIMMS I used, first I had A2 and B2. Swapped to A1, B1 and made sure the GPU was seated correctly.

I am pretty sure I have all the connections correct for the power switch/reset/HD LED. So, now I'm lost and he's freaking out cause he wants to play on his new PC

Can alone give me some hints on how to trouble shoot so I can get this to you up and going?   
Any help will be much appreciated!!!

Thanks in advance

Roll