There will be other people who will argue about this, but if you read the feedback from Pr0tel users you will find that the greatest number of those who have display problems are those who use ATI graphics cards.
It is, indeed, most likely that your graphics card drivers are at fault. If you are going to use ATI, update the graphics card bios and the driver software to the latest available.
In my opinion, you are better off with Nvidia or Matrox graphics cards for EDA software. It has been my experience that the ATI cards are great for gaming, but not so great for 2D design.
Your Pr0tel problem is definitely NOT direct X or open gl related.