A:Answer It all comes down to what you're using your monitors for. Are you using all 3 for some kind of racing game? Maybe an FPS? Or maybe an RPG? A 1070 can run most games, but fast paced graphic heavy games are more suited for the 1080.
While the 1070 can run 3 monitors, in the long run the 1080 will last longer in comparison with future games. It also depends on how much you're willing to spend. The 1080 dropped in price since the 1080 TI just came out so it's worth it in the long run. But if you're tight on cash, the 1070 will suffice.
