Got them running around 666 sol/s or 10200 sol/s total now as I dropped the powerlimits to reduce heat and noise. I have mostly founder's editions as well as a few gigabyte gaming OCs, 2 gigabyte turbos and two pny 1080ti blowers. Overclocks don't really have so much affect on hashrate with equihash I believe, but everything is running at 150+ core and 450+ memory.
Equihash can be wierdly picky about overclocks, sometimes MORE overclock gives less hashrate.
It doesn't seem to be super picky about memory clocks though.
My GTX 1080 ti Aorus pulls 620 sol/s at 150 watts (60% tdp) for a bit over 4.0 efficiency - which seems to be it's most efficient point or very close to it's most efficient point.
GTX 1070 ti (I got my EVGA SC today) at 60% can manage quite a bit better than 4 - more like 4.4 - at +200 core +700 memory in afterburner (but the card UNDERCLOCKS the memory by default a little for some reason).
Up side of the 1080 ti though is rig density and fewer cards to deal with, even if it IS a little less efficient than some of the alternatives.
Would you mind sharing what are your core&mem overclock settings for the GTX 1080 ti Aorus 620 sol/s at 150 watts (60% tdp)? That s pretty good number you 've got there.