Flip 3D/live thumb nail refresh problem

[JH]

I notice that when I leave some windows open for several hours without
bringing them into focus, and then try to use flip 3D, some of these windows
have no preview of the window contents; they just show a blank window with
an icon in them. The same thing happens when you try to bring up a live
thumbnail by mousing over the window on the taskbar.

I am running Vista Home Premium with a Opteron 165 dual core, 2 GB of RAM,
and a x800xl 256 MB video card. My Windows rating shows at 4.9.

Any idea what is causing this and how to correct it?

Thanks

 

[Andre Da Costa[ActiveWin]]

I see this also, but its after a period of inactivity with the window
minized. It also occurrs when I do a Win + D command. (Vista Ultimate).