I'm not sure if I will be able to explain what I'm experiencing but I'll try. Sometimes (periodically) when trying to rotate my model using the middle scroll button, my model will freeze and I can see a transparent part of the model in the area where I click to rotate the part about. If I continue to scroll the tiny area of the transparent model will increase and I have to wait for about a minute or so and the part will then come back to normal but it will zoom out from the area where the model was frozen. This will happen about every 10 minutes. I tried to take a picture of the screen when this happens but I'm not able to get a good picture.
I am running SW2011 on Windows 7 using an M6300 Dell Precision Laptop with 8GB memory. I double check my Graphic Card and it is compatible with SW2011. This only started last week and I've been running SW on this laptop for about 8 months. Any Idea what could cause this?