xrandr not happy about external monitor

[Michele Mattioni]

Hello list,

I have a laptop with a Mobility 9000 radeon and an external monitor
form Acer 22inches.

I'm using an ubuntu gutsy and the version of the xserver-xorg-video-ati is
1:6.7.195-1ubuntu2

xrandr detect correctly the monitor:

[mattions at the-tux:~]$ xrandr -q
Screen 0: minimum 320 x 200, current 1680 x 1050, maximum 1680 x 1200
VGA-0 connected 1680x1050+0+0 (normal left inverted right) 474mm x 296mm
  1680x1050      60.0*+   60.0
  1600x1200      59.9
  1280x1024      75.0     59.9
  1440x900       75.0     59.9
  1280x960       59.9
  1280x720       59.9
  1024x768       75.1     70.1     60.0
  832x624        74.6     74.8
  800x600        72.2     75.0     60.3     56.2
  640x480        75.0     72.8     66.7     60.0
  720x400        70.1
LVDS connected 1400x1050+0+0 (normal left inverted right) 0mm x 0mm
  1400x1050      61.8*+
  1280x800       60.0
  1280x768       60.0
  1024x768       60.0
  800x600        60.3
  640x480        59.9
S-video disconnected (normal left inverted right)

However I can't see any image on the screen.
The screen is somehow blue, and if I give the instruction like
[mattions at the-tux:~]$ xrandr --output VGA-0 --off

the screen turns black.
So I guess it's responding.

My Xorg log is here:
http://www.ebi.ac.uk/~mattioni/log/Xorg.0.log
Do you have any idea?

Thank you.

Cheers,
Michele