I've noticed that certain Aero animations, especially the fade-in effect when logging into Windows, are very choppy. How come these transitions are not smooth? Even much slower GPU's can handle these effects without effort. I have the latest drivers, and no problem playing HD movies or games, but this annoys me every time I boot the PC.
This type of issues could be related to the graphics driver outdated, try testing the latest drivers for your graphics controller:
Make sure to select your operating system version