I have noticed though that my NVIDIA cards GTX1070 8GB are getting lower hash rates. They are both the same and I'm getting 19.2 MH/S and 25.8 MH/S.
I have previously used the included ZOTAC software for overclocking. (was getting stable 29 MH/S before)
Do you have any ideas why the hash rate is lower?
Same with all of my 1070 cards. As I understand it, it will become slower each time the DAG increases. I am stable with 26.25 - 26.9 for all 8 of my cards on HiveOS. +100 core, +1200 mem, power limit set to 132 (because these are plugged into a 1200w PSU.)