Anyone else have issues running more than 2 Radeon VII?

I am looking to get to a 6x Radeon VII rig, but am adding them slowly as I find them for decent price. I currently have 3 installed, but the system will only fully initialize with 1 or 2 active. It doesn’t seem to matter which 2 either. The computer will start up and go through its cycle with all 3 cards lighting up, but it doesn’t send any signal to the monitor. Then if I shut it down, unplug the riser on one and it boots up fine. As I said, any combination of 2 will boot up fine and the cards are recognized. How the hell am I supposed to get 6 going? :frowning: I thought about it being a power issue, but at full mining they only pull about 250W each so with 3 and the system it is only about 1000W.

Im running

ASUS ROG STRIX B450-F GAMING AM4 AMD B450 SATA 6Gb/s ATX AMD Motherboard
Ryzen 5 3600
1 x 8GB RAM
1600W PSU
On risers with server power