Maybe you have your screen refresh rate low, to chech this you right click on your desktop, goto properties, then settings, then click the advanced button and set you screen refresh rate to the highest it can go without a problem, I have mine at 85 herts. Thats just a guess, or maybe you do have a virus and you have to use system recovery.
(I've never tried this for this before) You could also go to start, all programs, PC help and tools, and then click system restore and restore it to an earlier time, not sure if that would work for a virus but Im pretty sure it would work if you just screwed it up somehow. Hope this was helpful. PS. use systerm recovery as a last resort! Now get out there and bash that problem
