I have the same exact card. Currently hashing at around 31mh/s using claymore 11.5, my bios setup are core clock 1050, memclock at 2100, I have to lower memclock to one card to 2090 because of mem errors. And I'm using Trixx to undervolt and getting 910watts for 6 cards in dual mining and about 770watts in ETH mode.

https://s17.postimg.org/bmu8337in/claymore1.png