I have the same problem with my rig, mining ETH+DCR with Claymore 10.6v.
I randomly get WATCHDOG: GPU hangs in OpenCL. I switched to ETH only mining to reduce the stress, but it's not the power consumption which makes the trouble, nor the OC or undervolt; tried several adjustments.
BTW. I have a Gigabyte GA-H110-D3A.
I will try to reconnect the risers on the MOBO.
I get the error on random GPUs not always on the same.
I will update the post if the replug works or I find a solution.