Quote - I get the same effect with an nVidia GT240 with 1GB Ram so it's not that

Did you try right clicking in the working window and picking another viewing option than what you are currently runnin? IE: ScreeD instead of OpenGL or vice versa?  You can't say it doesn't work until you have at least tried :)

"It is good to see ourselves as others see us. Try as we may, we are never
able to know ourselves fully as we are, especially the evil side of us.
This we can do only if we are not angry with our critics but will take in good
heart whatever they might have to say." - Ghandi