hi, 4 days ago i buy a KFA2 GTX 1070 8GB, i get 420sol/s on zcash yesturday, and today i only have 60sol/s...

i check in afterburner, i get only 139mhz gpu clock instea of 1750+.
i remove the gpu of my rig to test it on my main computer and i have the same problem, so it's really about the GPU.
i try to update gpu bios but it does nothing, please help me!

edit: change the bios seem to move the clock to another value, but the gpu stand in idle.