Power issue? Driver issue?

Working with a small rig of 3x 1080ti. 2 are EVGA and one is an MSI Duke. I have had the rig set up with all 3 cards mining. Decided to move the rig and update to latest HiveOS. In doing so it seems I can only run 2 of the 3 cards at a time. With 3 cards I get weird problems, Hashing hangs up, cuda faults, random restarts, unable to detect fans. I tested each card individually and they all work. I tried different combinations of card pairs and they work in different pairs just fine. Then I put all 3 in the rig and the problems return. PSU is an EVGA Nova 850. I have another PSU on order and plan to add more cards to the rig. Any other ideas or thoughts I might be missing here as I trouble shoot? TIA

at least need to show result of execution nvidia-oc log