Some words about 1080ti Zotac AMP Extreme and gtx 1080:
Stable 57 mh with 315 watt tdp ( from psu ) -i 26 sp-mod 4
sp mod 5: same clocks etc.. :
ccminer64 - slightly speed as sp-mod 4 -i 26 ( gtx 1080 same speed )
ccminer (x32) -i 26 doesn't work for me, with -i 25.6 - same speed as sp-mod 4 ( gtx 1080 lower hashrate )
P.S Can confirm 1% speed boost for 1070 and 1060.
P.P.S sp how can i help you to tune 1080 and 1080 ti cards?