Quote Originally Posted by cairnswm
Actually I dont think the screen was being cleared at all - I had a black screen with some very retro looking blocks all over it

Change the GraphicsDevice.Clear statement to
Code:
  graphics.GraphicsDevice.Clear( Color.CornflowerBlue );
and you'll have the correct CornFlower blue of the empty XNA GSE base project.

I've changed the above base code as mentioned, though it would be nice to know why the other Clear code does not work.