None of my gpus are in actual board sockets all are on risers.
None of mine are in board sockets either. I use flat ribbon cable risers, with molex connector and caps. Btw, I prefer small rigs setups, with 4 gpu max.
I refuse to accept that all my rigs with Sempron140 from 2013 can handle 4 gpus, and this Ryzen 3900X setup on a x570 mobo cant cope with 3.