hopely this will help you, if all your hardware don't have a problem from PSU,cable, and riser, instal the lastest driver ( in my experience for multiple GPU wait until finish all instal the driver), restart, and run MAB set default for all setting accept fan speed as you needed at your temp room, and then run claymore v.9.1. If still get hang try setting your intensity one by one from 5, 6,7 or 8.
I did all those steps, but no use. And yes, I have latest catalyst 16.11.2, I even low intensity to 4. May I ask about your hardware, like CPU, Mobo, PSU, RAM, and OS? I read from above that it need 80 bronze cert PSU, im not sure if that's the problem, or from my OS.
Just my .02, but I believe the default intensity is 4. I could be wrong, but I have set -i 4 and my hashrate is same as default without setting intensity. Try backing it down to 1 or 2, then try to get up to 3 and see what runs stable.
Also, suppose you have a 1000 watt bronze psu and 4 RX 480's running. 150 watts per card. They actually use much less, but that would be 600 watts. Then your cpu is maybe going to be pulling 100 max, and that's if it ever gets to any kind of load... You'd have lots of headroom. Unless you're trying to run a 6 card rig on 1000 watt psu lol.
I have 2 x 750W PSU, each PSU runs 3 cards.
I dont blame Claymore 9.0 or 9.1, I had this problem since the first time I use claymore, since 5.0. There will be 1 card always not working, will hash 0 H/s. After a certain of time, watchdog says that GPU hangs and reset.
No matter how many GPU I use, there will be 1 not working.
My temporary fix was keep rebooting until all GPUs working, but now that ways seems not work anymore.