Bug#444223: xserver-xorg-video-ati: RS480 (radeon express X200G series): display goes to sleep after upgrade to latest unstable/sid

[Brice Goglin <Brice.Goglin@ens-lyon.org>]

Junichi Uekawa wrote:
>> Does it help if you disable DRI?
>>     Option "DRI" "off"
>> in the Device section should do the trick.
>>     
>
>
> Actually no. 
>
> I am suspecting more of it trying to output to something weird.
>
> How can I run xrandr to debug this problem when I can't see the
> display?
>   

Do you have ssh access from another machine? If so, 'DISPLAY=:0 xrandr
...' should work (with 6.7.19x at least).

Also the log should tell you which modes are available and which one is
chosen by default. You can force another one with PreferredMode, see
http://bgoglin.livejournal.com/10423.html

By the way, 6.7.192-4 is old, there's 6.7.194-1 now :)

Brice