I installed beta F9 few days ago, and getting the same error than I installed F8 on my notebook.
I have a ZT3000 Pavillon notebook, with 1.5 Centrino - 1Gb ram and a Mobility Radeon 9100 IGP.
Now, when I turn on the Desktop effects I get a part (the right part) of the screen unusable like the effects only apply to a 4:3 resolution.
I use the native resolution 1280x800 (the effects worked fine in f7 with Beryl) and the effects only refresh a part of the screen I think refresh only 1024 x nnn.
I don't know the configuration file I need to edit to correct this problem in the Xorg file or in the compiz fusion file.
Thanks! any comment will be appreciated.
Ps: If you need two screenshots with and without effects, let me know and I can do that tonight!