I replaced the 7 deltas with gentle typhoons in order to make the rig suitable for in the house. I am currently running 2 1080ti founders editions, 2 1070ti founders editions and a 1070ti mini. Temps are 60 or below on all cards and the rig is pulling 880w at the wall. I am very happy with this setup now that the fans are quieter.

P.S. Octominer, please do not cut the cables on the deltas in future batches. I would have preferred to have the option of using pwm control rather than just a Molex connection.  I would also recommend a grill above or below the psu mounting location to provide for better air flow to the psu.