Can you give us the complete model code? This is located in the Main menu under support> Contact Samsung.
Also, what type of HDMI cable are you using? Is it a 2.0 version or higher?
The screen Samsing 7100 4K TV goes blank for 2 seconds, sometimes 1-2 times in a row. May not happen a day and may happen 2-3 times and even 20 times a day. Used as a PC monitor, connected to HDMI2.0 port via videocard GTX880TI