I went further to test with radeon driver from https://launchpad.net/~xorg-edgers/+...e/drivers-only. I have now the PPA added to software sources and the system updated.
Without KMS the DVI-0 is not recognized. With temporarily added boot option to grub radeon.modeset=1 I get the same 1024x768 picture to both panel and DVI-0! Xrandr reports this:
The problem is now that every attempt to change video mode results to somehow horizontally out-of-sync mostly white video looking crap, e.g.
Screen 0: minimum 320 x 200, current 1024 x 768, maximum 8192 x 8192
VGA-0 disconnected (normal left inverted right x axis y axis)
LVDS connected 1024x768+0+0 (normal left inverted right x axis y axis) 287mm x 215mm
1400x1050 60.0 + 50.0
DVI-0 connected 1024x768+0+0 (normal left inverted right x axis y axis) 0mm x 0mm
The same happens with native 1680x1050 for LCD that I'd like to use. For some reason it's not in the retrieved EDID modes list. Fortunately I'm able to get now thanks to KMS a sane console with alt-F1 so I can shut down X properly.
xrandr --output DVI-0 --mode 1360x768
Here's again the log http://pastebin.com/m415cd9d0
Is there something else I need to update to get radeon and DVI work properly? Kernel (now 2.6.31-11-generic)?