I just replaced my old 1600 x 900 monitor with a new Sceptre television.
Sceptre U435CVUMC 43 4K Ultra HD 2160p 60Hz LED HDTV 4K x 2K

My old AMD Radeon 6950 could not do such a high resolution so I got a new GTX 970 graphics card.
EVGA GTX 970 4GB GDDR5 04G-P4-2972-KR 2DVI/HDMI/DisplayPort PCI-E Video Card

When I use the TV over HDMI I can get everything fine at 30Hz. The stickers next to the HDMI port all say 60Hz so I figured I should try it. Usually when I switch to 60Hz the display goes blank. Sometimes when I switch to 60Hz then restart the power to the TV it'll go on, but only for about 10 seconds and I will see some green pixels in some places and some of what look like scan lines in some places, all of these artifacts flickering, then it goes blank again. I have the latest Nvidia drivers, and the AMD drivers are fully uninstalled. I have tried switching to 60Hz both within the Nvidia graphics driver settings and the Windows 8.1 Screen Resolution Advanced Settings.

For now I guess I'm stuck with 30Hz until somebody helps me. I'm sure that the TV can handle 4K at 60Hz so I really think it's my graphics card or drivers, but I can't solve this on my own.

My OS is Windows 8.1 Pro x64