Non-persistent screen resolution

[Andrew Kane]

     I'm running Ubuntu 8.10 on an older Athlon system with Radeon
9200 graphics, using the "radeon" driver. When I log into a new
session, the screen resolution is sometimes not the same as it was at
logout.
      I typically run at 1600x1200, and the session will start at
1152x864 or lower. The "screen resolution" dialog only lists a
possible refresh rate of 60 Hz, even though I have modified my
xorg.conf to reflect the VertRefresh and HorizSync values correct for
this monitor, which should be capable of 160Hz.
       After changing the screen resolution to the maximum listed
value of 1280x1024, the screen shrinks into the upper-left corner and
the right and bottom edges fill with garbage. At this point I
typically kill the server with ctrl-alt-backspace and log in again.
       After login the new 1280x1024 screen displays correctly. The
screen resolution dialog then offers 60Hz and 75Hz refresh rates, and
resolutions up to 1600x1200. If I change to 1600x1200, I get the same
"garbage" problem, which seems to occur with every upward change in
resolution.
       Hopefully someone can help me to troubleshoot this. I haven't
filed a bug because I'm not sure whether this is a hardware problem or
something wrong with the "radeon" driver which afaik is not maintained
by Ubuntu. Any help is appreciated- thanks for reading this.