I think it really depends on your specific PSU, type and number of cards that you are using. Seen as it will be pretty much running 24/7 for several years (hopefully), it is not something I would want to take any changes on.
For the rig I am building I have 6 * GIGABYTE AMD Radeon RX 580 GAMING 4GB GPU with a Corsair RM1000x PSU.
From what I have read I have decided to get rid on the risers with the SATA connection. And go for the type with 6 pin molex connectors like the following:
https://www.ebay.co.uk/itm/6X-USB-3-0-PCI-E-1X-16X-Extender-Riser-Card-Adapter-Power-Cable-ETH-BTC-Mi/273138536150?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2060353.m2749.l2649Are those safe for long term use? Numbers would be preferred to anecdotes.
My main issue is that the PSU doesn't come with enough cables. I have enough to power the GPU's but I am not sure how I will go from the PSU to the risers.
Is there such a thing as a cable with an 8 pin adapter that will fit into the PSU and 6 pins that will fit into the riser end. Is it ok to just buy separate cables, I have read that you should just stick with the cables that the PSU manufacturer provides.
Many thanks