Here are my settings:
Power Target 110%, cgpu +75, mem +500, voltage 1050mV, and I changed the fan speed map. I put the fan speed at 50% for 70c and it goes linear up to 100% at 80c. It doesn't go past 71C and is still quite.
My case's airflow is:
2 120mm 79cfm intake front
1 140mm exhaust top
2 120mm 79cfm in push/pull with radiator exhaust out the back.
You used EVGA precision then? If so, maybe I'll try it. I used MSI afterburner and haven't played w/ voltage yet.