When zooming and/or panning in drawings and/or assemblies, the screen/view port/picture does not always update.

i.e. It remains showing the image as it was before zooming/panning until I click rebuild OR press "f" key to zoom-to-fit OR wiggle the mouse around until the picture/view refreshes.

It is not a case of "lagging"

It is almost as if something is causing the program to "forget" to refresh/update the screen.

I have tried complete uninstall and reinstall.

I have also tried resetting the registry for SW.

Any suggestions?