Created attachment 96797 [details]
Screenshot

Hello,

Each time I tried to use the free radeon drivers with my desktop computer, I
got those corrupted pixels when X starts. The issue effects increase as the
session time grows: more and more artifacts, more and more character
alterations (for instance, Thunderbird is displaying blocks instead of
characters), more and more instabilities (programs ends up by a segmentation
fault, and could eventually lead to a system freeze).

Otherwise, Gnome Shell starts without error. `glxgears` works and returns good
FPS. And the virtual consoles remain safe & clean; switching between them and X
has no effect.

The system was stable, without screen corruption when I used the AMD’s FGLRX
drivers.

How could I fix this issue? Any idea?
This ticket seems quite similar, should I try the proposed patch?
<https://bugs.freedesktop.org/show_bug.cgi?id=66932>

Chipset: AMD Radeon HD 6570 (Turks family) with 512MB dedicated RAM (AFAIR).
CPU: Intel DualCore E6300 with 4GB RAM.
Kernel: Linux 3.13-1-amd64.
And I use the defaut Xorg configuration (i.e. no configuration files).