I'm running a fairly new installation of Saucy on a (mostly) stock DELL Dimension 9150. My menu bar started flashing today; actually, the upper quarter of my screen flashes erratically unless I'm running a fullscreen application. The Unity menu also refuses to show. I can search and launch applications on it, but I'm flying blind with it.
I'm new to Ubuntu but not computers in general, so I did some searching and found my graphics card, a Radeon X300, is supposedly supported well under the default open source display drivers, and the fact that the flashing stops with a fullscreen application AND the fact that the Unity menu stopped appearing around the same time would lead me to guess it's a Unity issue. I've looked through lots of other Unity problems but couldn't find my exact problem and none of the solutions I've tried have worked (unity-reset, unity --replace, etc.).
Thanks in advance for your help!