I have the same problems but mine happen when I switch views, they appear for just a few seconds then go away. But it is annoying. Maybe someone can help.
It could be a problem between the new driver set and your card. Try reverting to an earlier set and see if this cures the problem. Several people have had trouble with the latest update.
Ozzy
There are two types of aeroplane, Spitfires and everything else that wishes it was a Spitfire!