Hi iam using Gigabyte GA-H110-D3A with 5 GPUs for now Sapphire Nitro+ RX 580 8GB iam waiting for one more, i was going to ask you about the molex connectors on the motherboard what are they for and do i need to plug them in ?
motherboard molex is for GPU PCIex16 power, if you would use powered riser there is no need to plug this. just use a decent USB powered risers with 6pin power connector.
https://www.amazon.com/gp/product/B076KLJR2Y/ref=oh_aui_detailpage_o01_s00?ie=UTF8&psc=1