So you assume that he got 187 Mh/s from 6xRX580 with compute mode off? 
I think noobs account should not be allowed to give advice, only ask...

to answer OP: looks like clock and/or voltages are not properly applied, because power draw for phoenix is about the same as for claymore. And with that I refer you to  posts on this and previous page: "ALWAYS use 3rd party soft to control clocks, power and fans: OverdriveNtool for red and nvidiaInspector for green; don't use AB - it's shit. Don't use miners for controls."