Got 4 of them in 2 h110 boards. They needed 1200 PSU and all summer they throttled down to 22Mhs each. 2 XFX and 2 Sapphire cards. Sapphire got better thermals but all of them got to 30Mh/s with 1090 core and 1300 memory. But... on open air rigs, they manage to melt all 4 PCI riser SATA connectors, and all of the 8pins. I was using push/pull SP120 fans on all the rads, but the cards could not stay below 72-73 at best. The 120 rad is way too small for the dissipated heat. I now kept 1 of them, watercooled with custom waterblock, added a 240 rad and the card is working grat at 56-57 max temp.

I would not recommend using risers with low AWG cabling, and for sure do not use the SATA connection. Use 6pin power for the risers.
Also cool the backplate of the cards with as cool air as you can, or else you are going to burn the 8pin power connectors in a matter of days, rendering the card almost useless, unless you want to use custom wiring soldered to the cards.