In the manual for the Samsung 4K PVR it shows how to change the resolution of the terminal. It also says "For Ultra HD, your TV's auto resolution function will automatically select UHD/4K resolution for you".
Does this mean that if you have a 4K TV, even if you set the resolution to SD or HD, it won't stay like that but the TV will change it to UHD/4K?
What that means is that the terminal will automatically set itself to UHD/4K when it will detect that you have a 4K television. After that, you can choose the specific resolution manually if you prefer.