I create a Window XNA game project from the template in Visual studio 2015. Then I right click and set the property to console application because I think it is convinient to use Console.WriteLine() for debugging.
In the game constructor I add
graphics.PreferredBackBufferWidth = 1920; graphics.PreferredBackBufferHeight = 1080; graphics.IsFullScreen = true;
Now the console text flicker. I use Console.Clear() the first thing I do in Update(). When I run the game in a window then the console text do not flicker. I even add counter to not update the text every time Update() is called and the console text still flicker in full screen mode. The same problem is there when I start form Windows Powershell. (The exact same thing do not flicker with MonoGame though.)