It works. Haven’t bought a graphics card since the mid 1990s, but did this because Gnome 3 feels a lot smoother with some extra cycles and memory. All the eyecandy effects now seem to run at around 20 fps, and the colors are nicer. Before, they were more like 10 fps and jumpy. This shows up in lspci as VGA compatible controller: Advanced Micro Devices, Inc. [AMD/ATI] Caicos [Radeon HD 6450/7450/8450]. Seems to be a bit of a power hog, but it doesn’t use a fan, so it’s not going to burn too much coal.
Also, programs run a little smoother because the memory isn’t being shared with a graphics controller. The main effect, though, is that the corner, where you push to get the task switcher/menu and the application shortcuts, comes up in around 1/4th of a second instead of one second. That makes a difference.
Free vs. Proprietary Drivers
You can choose to run this with the Free drivers or the Proprietary drivers. The free ones work well, but the proprietary ones will give you faster effects. I can’t quite tell, but it seems like the window manager is a little slower with the proprietary drivers.
Youtube/Flash videos interact better with the proprietary drivers.
Video games seem to run faster with the proprietary drivers, but the windowing system starts lagging after you run a video game, so the games probably use up all the memory on the card.