OpenGL green line
On some Apple models you see a green 1px line at the bottom and right side of the video window. When you double the size of the windows those lines are doubled to 2px and additional 1px lines are added at the top and left side of the view. It is probably a difference in OpenGL implementation for radeon and nvidia that makes this problem only show on some models (radeon). Probable causes lie in the size of the OpenGL render plane. Of interest is to note that if you enable cube renderering the lines are visible on the edges of the cube as well.