Vukak,
It just looks that way because the X dimension is so wide. His resolution is 6000x1200 instead of my 1920x1200 (for example).
The Y dimension (height) is determined by the native resolution of your monitor. In my case as with Rockdog's, our native resolution for a widescreen monitor is 1920x1200 which means that the height would be fixed even if he had four or five monitors arrayed along the X dimension.
Hope that makes sense. If he could have five monitors for example (two on each side), his "screen resolution" would be 4x1920 X 1200 = 9600 X 1200. That would be rather obscene of course.
