Sata Powered GPU Risers

Hello, so I have 4 RX 570s and 4 sata powered gpu risers version 007. I also have an EVGA 850w Gold G3 PSU. I was wondering if it is safe to use the risers? I have connected the sata cables from psu to risers directly, no adaptor. Have also connected 8 pin from psu to each gpu of course. I have kept the rig running for 1-2 days and have not seen the cables get hot or anything at all, but I do want to ask if this is safe to do and should I keep doing it.

If its of any help to you at all i have 6 1070s on the same risers and all the cards are OCed and i have had zero issues… My rig has been going for almost 3 1/2 months no heat issues with the wires or anything…