The motherboard HDMI port is usually disabled when you install a video card and not all 1070s come with dual HDMI ports.
Finally what are these TVs? I've see dead ends over old 720p sets. Let's get some details into your discussion.
I have two TV displays with HDMI ports for hookups. Both work when plugged in by themselves but when I try to plug the second display in it fails to recognize the display. I have updated the drivers on the displays and graphic card, and run through the options for enabling a second display in the display menu as well as the Nvidia menu. Nothing seems to work. I also made sure the second display was turned on and on the correct input. Any help is greatly appreciated. I have a GeForce GTX 1070TI graphics card, 16GB mem, Intel i7 3.70 Ghz processor on win 10. If you need any more info, just ask.

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