AMD has released a statement about it's Polaris cards using more power than they are meant to.
http://www.anandtech.com/show/10465/amd-releases-statement-on-radeon-rx-480-power-consumption
"As you know, we continuously tune our GPUs in order to maximize their performance within their given power envelopes and the speed of the memory interface, which in this case is an unprecedented 8Gbps for GDDR5. Recently, we identified select scenarios where the tuning of some RX 480 boards was not optimal. Fortunately, we can adjust the GPU's tuning via software in order to resolve this issue. We are already testing a driver that implements a fix, and we will provide an update to the community on our progress on Tuesday (July 5, 2016)."
In other words, they will fix it with a driver update. There will likely be BIOS updates as well for some cards.
www.youtube.com/@Pemalite
