NVIDIA driver v396.24.10
clockOffset = 100 and memoryOffset = 1000 @ PL=220 W for 1080Ti
1070Ti with EWBF v0.6 delivers now 49 to 55 sols/s
clockOffset = 200 and memoryOffset = 1200 @ PL=120 W for 1070Ti
efficiency = 0.45 Sol/Ws
Which is your 1080ti model? You did great job with mem + 1000. Are they stable with mem + 1000?
ASUS 1080Ti with three fans. Very stable, but do not increase clock offset!