GPUs shutting down

Hello all,

I setup first rig with:

MOTHERBOARD ATX GIGABYTE H110-D3A

CPU Intel Core i5-7400 Quad-Core 3.0GHz c/ Turbo 3.5GHz 6MB Skt1151

RAM G.SKILL Aegis 8GB (2x4GB) DDR4-2400MHz CL15 black

SSD M.2 2280 Samsung 860 Evo 250GB MLC V-NAND SATA

Seasonic PRIME Ultra 850W Titanium Full Modular

Gigabyte GeForce GTX 1080 G1 Gaming 8GB - 2 of them

It can do about 1100 sol/sec but after 1h of working the gpus are shuting down. The temperature of the GPUs are about 69 ºC.
There are two molex entries side by pci-e in the motherboard, should it be plugged?

What can I’m doing wrong?

Thanks.

if you are only running two gpu’s in the main GPU pci-e slot, then no. Those are for additional power when running multiple gpu’s to make sure everything is getting powered correctly

About My Setup

Riser Version
Overclocked (Yes or No):
Overclock Settings:
mining software
Additional Information (Please include bat or config settings):

In addition to what the last poster ask.
Are you plugging these cards right into the ×16 slots on the motherboard, or are you using risers?