so that's what happens... all three HBA's work only in slots 2,4,6. If in 1,3,5 they don't show in proxmox.
With them in 2,4,6 and I put the nic in slot 5, I lose 2 of them.
I'm just struggling with Supermicro in trying to understand that they would have a brand new board in 2020 that has 6...