that's just the core at 82w, the vrm uses another 70w..check it with aida64
my rx570 elpida @ 900mV uses about 150w for solo 28MH/s eth with core on 1132MHz, mem on 1975MHz..and 180w for dual 28MH/s eth + 280MH/s pasc
this seems values more credible!!!
GPU 80 watt are just a part of the power consumption...