Dual link on X1250 radeonhd git head fails

[Alex Deucher]

On Thu, Mar 20, 2008 at 2:51 AM, Adam J. Richter <adam at yggdrasil.com> wrote:
> On Mon, Mar 17, 2008 at 02:42:40PM +0100, Matthias Hopf wrote:
>  > Current git of radeonhd should support dual link DVI as well, though
>  > this is untested ATM.
>
>         I just tried the radeonhd git head (pulled minutes ago) on a
>  30 inch 2560x1600 HP lp3065 monitor, and the screen is black with the
>  green LED flashing.  This same screen displays BIOS messages, lilo
>  text and the character mode linux console fine, as I think there is
>  some built in video stretching done in character mode (for example, in
>  character mode, my 1920x1200 monitor always claims to be receiving a
>  1920x1200 signal rather than 640x480 or something similar that one
>  would normally associate with character mode).  xrandr, correctly
>  describes the video modes for my 1920x1200 monitor on the VGA cable
>  and the 2560x1600 monitor on VGA, and indicates that 2560x1600 is
>  selected, and the virtual screen size is expanded to 2560x1600.  So, I
>  think this is a mode setting issue and not some misconfiguration on my
>  part.
>
>         My new lp3065 can select between three dual-link DVI input
>  cables, so I should be able to plug it into an nvidia card for now to
>  use it immediately while still being available to test new changes
>  through a cable connect to my AMD motherboard.  So, if anyone wants me
>  to try a patch and report results, I am happy to do so when I have time.
>
>         Also, if anyone would like to point me to the relevant page
>  numbers of the recently released X docs for the rs690 in
>  http://www.x.org/docs/AMD/ for enabling dual link, I may be able to
>  try to work on this myself during the weekend.  I had previously
>  skimmed AMD's recently released documents but didn't immediately find
>  a bit to set to activate dual link.

Have you tried radeon?  Also, your board may not support dual-link.

Alex