[SOLVED] ATI X1550 Radeon Widescreen Video Resolutions Fuzzy on Dual DVI Card

sysfce2 · 01-12-2010, 12:17 AM

Hello,

I am trying to get a second widescreen video monitor working on my dual DVI card (ATI Radeon) running under Slackware 12.2.
Lower resolutions (up until and including 1280x1024) work fine and are clear, but once widescreen video is selected the video appears 'fuzzy'.

The primary display works fine (as does plugging the second monitor into the primary DVI output).

Any suggestions as to how I approach this from here?

Here are the relevant documents:

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EDIT: Removed list of mostly irrelevant info (xrandr output, lspci output, partial xorg.conf)

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I call this script from the last line in xinitrc

#!/bin/sh
xrandr --newmode "1920x1200" 193.25 1920 2056 2256 2592 1200 1203 1209 1245 -hsync +vsync
xrandr --addmode DVI-1 1920x1200
xrandr --output DVI-0 --1920x1080 --output DVI-1 --1920x1200 --left of DVI-0

sysfce2 · 01-16-2010, 12:52 PM

Well, this was a tough one, but I got it figured. Seeing as nobody seemed to have any ideas (or I phrased my question poorly), I'll post the solution - hopefully it can help someone else.

The key was that I had to generate a modeline for an undetected output and add it manually.

However, I used 'cvt 1920 1200' to generate the modeline.

The modeline didn't work well with my display so I started X as follows:
'startx -- -logverbose 6'

Then I found this in '/var/log/Xorg.0.log':

Code:

Supported Future Video Modes:
(II) RADEON(0): #0: hsize: 1600  vsize 1200  refresh: 60  vid: 16553
(II) RADEON(0): #1: hsize: 1280  vsize 1024  refresh: 60  vid: 32897
(II) RADEON(0): #2: hsize: 1280  vsize 960  refresh: 60  vid: 16513
(II) RADEON(0): #3: hsize: 1152  vsize 864  refresh: 75  vid: 20337
(II) RADEON(0): Supported additional Video Mode:
(II) RADEON(0): clock: 154.0 MHz   Image Size:  518 x 324 mm
(II) RADEON(0): h_active: 1920  h_sync: 1968  h_sync_end 2000 h_blank_end 2080 h_border: 0
(II) RADEON(0): v_active: 1200  v_sync: 1203  v_sync_end 1209 v_blanking: 1235 v_border: 0
(II) RADEON(0): Ranges: V min: 56  V max: 75 Hz, H min: 30  H max: 81 kHz, PixClock max 170 MHz

So I used those values to create the modeline and it now works.

Complicating matters was that running the xrandr command at the end of xinitrc did not work: I have to run the script again manually once KDE has started.
If anyone has any ideas on how I can automate that it would be great, but it is not a big deal as i have set up a shortcut key so I can run it easily.