I will share my 1080ti settings for best results in zcash mining with you guys,

Power Target to 65%
GPU Clock Offset +60
Mem Clock Offset need to be figured out be everyone self.

With these Setting I have less power and a better soll to power ratio with my 1080tis

What it does you just undervolt and overclock your GPUs
In some times you need more mem but you can play around with the setting till you find your sweet spot.