Comment 7 for bug 150627

Re-opening, I've got a similar problem, and I can't see the similarity with bug 150361.

I installed the driver using the instructions at http://wiki.cchtml.com/index.php/Ubuntu_Gutsy_Installation_Guide#Method_2:_Install_the_8.42.3_Driver_Manually. Now, whenever I start Firefox (v2.0.0.8), I get visual artifacts in the bottom right corner of the primary screen (I've got a dual screen setup with horizontal,reverse). It's kinda hard to explain how it looks, so here's an attempt at ASCII graphics:

|#|#|#|#|#|#|#|#
|#|#|#|#|#|#|#|#

|#|#|#|#|#|#|#|#

|#|#|#|#|#|#|#|#

|#|#|#|#|#|#|#|#
|#|#|#|#|#|#|#|#

Legend:
Pipes (|) are green or something similar lines which are all 1 px wide, and which are sometimes broken in some places by black.
Hashes (#) are black and all about 10-15 px wide. The height of the top and bottom horizontal bars are about 20 px, while the middle ones are about half that. The middle gap is about the same height as the middle bars, while the top and bottom gaps are slightly thinner (maybe 6 px). The desktop contents are visible in the gaps.

The artifacts stay in the same place even if I move the Firefox window.

The artifacts do /not/ show up in a screenshot of the entire desktop.

More interesting, the artifacts /disappear/ if I open the ATI Catalyst Control Center and press "OK" there. They reappear the next time I start Firefox.

I did /not/ have this problem with the previous version of the driver (8.40.something).

Hardware:
$ lspci | grep 01:00
01:00.0 VGA compatible controller: ATI Technologies Inc RV370 5B60 [Radeon X300 (PCIE)]
01:00.1 Display controller: ATI Technologies Inc RV370 [Radeon X300SE]