Try it with it off. Be sure the video card drivers are current and the video card is HDMI 2.x.
Finally be sure the TV firmware is current. No reason to use PC Mode if you what UHD.
I just bought the Samsung KU6075 or KU6300 i believe its called in US ?
Anyway, i can't get it in 4K 60hz 4:4:4, when plugging it in my HDMI 2.0 port.
My settings are
Pc Mode enabled.
UHD color -mode-OFF.
With these settings i can get 4k 30hz max. If i set UHD color-Mode to ON, the screen turns green.
Everything works fine if i use a HDMI 2.0 to Mini DP 1.2 and plug it in my mini display port. Then i get 4k, 60hz 4:4:4 with UHD-color enabled. I`ve tried the computers HDMI 2.0 port on my other Samsung KU6400, and there everything is working fine, so i know the computers HDMI port is indeed 2.0, and the Windows 10 and Nvidia settings are correct. I`ve also tried several HDMI cables. Both High Speed HDMI 2.0 cables and regular cables.
This issue doesn't make sense to me. The TV works fine with the HDMI to MDP adapter. The laptop works fine with another tv. So where can the problem be ?
My computers relevant info:
GTX 1070
Windows 10 creators update.

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