For no apparent reason, parts of the text on my display have disappeared. Sometimes several words, or the bottom half of the words are missing. I presume this is a fault with the graphics software perhaps having been corrupted. I have tried rolling back the driver and then rolling it forward again but it makes no difference. Can anyone please offer an explanation and a cure? I use Windows Xp Sp3 with a Radeon 9600 Series software version 8.573.0.0.