Thanks for your suggestions Dave. I figured out it was my drivers that were the problem. I had the new 52.16 drivers installed. I reverted back to the 45.33 drivers and now Maya works perfectly, the viewports refresh properly now so all is good. Seeing as how I haven't noticed any significant improvements in performance of games etc with the 52.16 drivers, I may as well just stick to the 45.33 drivers until NVidia releases a new drivers version to see if they work. Thanks again, QwErTyKb