I have a GTX 1080 Gigabyte Waterforce.
Using msi afterburner.
Power limit 68% Core clock -400 (effective base clock 1620Mhz) Memory clock +985 (effective speed of 5593Mhz)
Stays at 46celcius
Using Claymore miner and ethereum I'm getting 26-27Mh/s.
Try the above settings but start with your memory clock at 400 and work your way up, watch your hashrate while you are doing this.
I say this because, as an example, you can overclock the ram to +800 but it will perform worse than at +400.
For some reason when I go above 985 on the mem power usage drops and the card goes to around 21Mh/s.
Hope this helps.
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