I'm curious if anyone knows why GTX 1070 performance has dropped on Eth. I still have a bunch of them on various Windows and Linux rigs. They all easily hit over 30 MH/s in the past and many were in the 32-33 MH/s range. Now, they are lucky to to hit 30 and many are 28-29. This is the case with both Claymore (with and without strap settings) and Phoenix. Oddly, my 8GB RX 580s still chug along happily at 30-31 MH/s (i.e. they don't seem to have been affected by whatever is responsible for slowing down my 1070s).
This is a known issue with nvidia unfortunately, the bigger the dag file, the slower they get. If not done already, increase the GPU OC (not memory)