Different 1080's where tested by go6ooo1212.
To get a boost up to 10% you need to play with the tdp and overclock and downclock the memory max.
6 cards rigs: (per card)
1080 FE: from 330 to 365MH (+10.6%)
Palit 1080 GameRock: from 365 to 384-7MH (+5.2 - 6%)
Palit 1080 SJS from 370 to 398 MH (+7.56%)
Rig 1: +210MHASH
Rig 2: +132MHASH
Rig 3: +168MHASH
...
I've tested a lot of Pascals today with SP_mod#3.
The approach is only 5-7% , according to several different models I have:
1080 FE - 6 cards rig from 330 to 365MH
Palit 1080 GameRock ( Without Premium) - 6 cards rig - from 365 to 384-7MH
Palit 1080 SJS - 6 cards rig - from 370 to 398 MH
Palit 1070 SJS - 6 cards rig - from 288 to 301 MH
So guess I'll be waiting for this 12% gain ...