Simplemining OC settings help

Hi Everyone,

I bought my first mining rig that consists of 3 GeForce GTX 1070s, a GeForce GTX 1080Ti, and a Zotac Amp Extreme 1080Ti (will be adding a GeForce GTX 1080Ti Gaming OC tomorrow). I have it running off of Simplemining with the 1080 OC settings as Core 110, Memory 100, Power 220 and the 1070 settings as Core 125, Memory 450, and Power 120. With the 5 GPUs I'm getting a total hash rate of around 2550 sol/s on Equihash. The 3 1070's are all around the same low 400s, but one 1080 is at 730 sol/s and the other at 510 sol/s. I've tried messing around a bit with the OC settings, but unsuccessfully as it would either make no difference in the hash rate or cause the rig to crash.

Any suggestions on how to tune the cards better, especially the 1080Ti that's only getting in the low 500s? Thanks!