ati xrandr: cannot find crtc for output DVI-0

[Jan Dittmer]

Alex Deucher wrote:
> On 8/27/07, Jan Dittmer <jdi at l4x.org> wrote:
>> Given ati driver 6.7.192 and libxrandr 1.2.1 (Debian experimental)
>> I cannot enable the DVI-0 output using:
>>
>> $ xrandr --output DVI-0 --right-of VGA-0 --mode 1280x1024 --rate 60
>> xrandr: cannot find crtc for output DVI-0
>>

[old xrandr output snipped]

> radeons only have two crtcs and you are trying to enable more an two
> monitors.  you'll need to turn off S-video in order to turn DVI on.
> 
> xrandr --output S-video --off
> xrandr --output DVI-0 --auto

Thanks for the quick reply. That indeed fixes the issue.

> If you don't have a tv plugged in than I'm guessing you probably have
> an analog monitor on DVI-0 which is causing the tv to detect load (TV
> and DVI port share the same dac).

Exactly. I've a dvi-vga adapter on the DVI port. With a DVI cable the
color temperatures of the monitors don't match (under windows).

A serious problem remains: The screen attached to the DVI output
is a lot brighter. All the aliased stuff around glyphs gets white so that
the screen is barely readable. All bright colors look white. Is this a problem
with some gamma processing? (I checked the monitor settings more than twice,
it's not correctable by lowering it's brightness or contrast)

Thanks,

Jan

$ xrandr -q
Screen 0: minimum 320 x 200, current 2560 x 1024, maximum 2560 x 1024
VGA-0 connected 1280x1024+0+0 (normal left inverted right x axis y axis) 376mm 
x 301mm
    1280x1024_60.00   60.0*+
    1600x1024      60.0
    1280x1024      59.9
    1280x960       60.0
    1280x800       60.0
    800x600        56.2
    640x480        60.0     59.9
DVI-0 connected 1280x1024+1280+0 (normal left inverted right x axis y axis) 
376mm x 301mm
    1280x1024      75.0     59.9     60.0*
    1152x864       75.0     74.8
    1024x768       75.1     70.1     60.0
    832x624        74.6
    800x600        72.2     75.0     60.3     56.2
    640x480        75.0     72.8     66.7     60.0
    720x400        70.1
S-video connected (normal left inverted right x axis y axis)
    800x600        59.9 +   60.3