ASRock H81 BTC Pro XFX RX480 issues

Hello,

I started building a rig yesterday and am having some early issues. This is my first rig.

I am currently using:
ASRock H81 Pro BTC
XFX RX480 Black edition
Celeron CPU
4GB Ram
EVGA 1200 PSU
6x Risers

5 of the RX480 risers are connected to the PSU by 4-pin to 8-pin.
1 of the RX480 riser is connected through SATA conversion.

When I turn on the rig, I get a black screen in most instances.

On some of the instances, I get a screen telling me to connect a 4-pin connector from the MOBO to the PSU. I can bypass this screen to my BIOS by pressing F2.

1 of my X graphics card's fans stops spinning after a few seconds. If there are 4 cards installed, 3 spin and 1 stops. If there are 6 cards, 5 spin, and one stops.

My question are, is this a BIOS problem (I have not tweaked it at all nor have I installed windows)? Why does one of the graphics cards stop spinning? Am I getting the message to connect a 4-pin connector from the MOBO to the PSU because I lack the power to power up all 6 cards?

Currently, the BIOS is set to run on PCI-E and not the onboard graphics card.

Any help will be greatly appreciated, thanks!