4k output problems

[Audioiguy]

I have a video issue. When I connect my computer (evga gtx 980 sc) to my surround sound stereo,which in turn is connected to my Samsung 4k TV I lose video as soon as windows loads. I believe the problem is that the video card is seeing the 4k TV and outputting a 4k signal however my surround sound stereo is not able to pass 4k signals through it

 

[popatim]

have you tried entering Safe mode and setting the resolution to 1080 manually?

 

[Audioiguy]

I can't get to safe mode in windows 10 because it won't get into windows. None of my Nvidia computers will work but any of my amd pc's work fine