You should download and install GPU-Z, which can be found here:
https://www.techpowerup.c...hpowerup-gpu-z-v1-12-0 And check if your GeForce GTX 1070 has Memory by Micron.

(I have marked the Memory type in red so you know where to look).
If it says Micron here (Hynix in my example), you will need to update the firmware of the card, as there is a known problem
with GeForce GTX 1070 and Micron Memory that can cause artifacts just like the ones you are seeing.
Firmware updates for Evga GeForce GTX 1070 cards can be found here:
http://forums.evga.com/EV...04500070-m2565056.aspx