It's been a few yrs. since built my last computer. Guess I've forgotten a few things.

New ASUS mb & AMD A8 3850 apu. System shuts off almost immediately. Take the apu out and it stays on. No beep codes.
Bought this as a package from Amazon.
SOLVED! There were 2 extra connectors from the power supply that I hadn't seen before. Turns out, they're needed to power the amd apu... it wasn't getting enough. Live and learn, eh!