MSI Z97 + 6x GIGABYTE RADEON RX580 not detecting GPUs

Hello all,

I just bought the parts for the my Ethereum rig and bought ethOS, everything boots good, but I for the life of me cannot get the ethOS to recognize my gpu0 (Gigabyte Radeon Aorus RX580)
My card is connected (they are all brand new and I tried 2 and they light up) via a riser (V7 USB3) and SATA power to the closest PCI-E x16 slot on the motherboard. Every time I boot into ethOS, the result is Mining GPU detected 0, check power or risers.

I have tried different risers of different brands, I for sure have the right connection on PCI-E and I have tried also connecting extra PCI-E power besides the riser power. Does the PCI-E power need to be connected to the GPU PCI-E or the riser SATA power is enough? I have also modified BIOS settings to disable onboard AUDIO, set PGE to Gen 1...everything stated for MSI/RX GPUs on ethOS website but nothing is working. I am using onboard video to get into ethOS since as I understand I am not supposed to get video with riser when booting up? Please help me as I have this hardware now and unable to boot or find any help.

Thank you so much.