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Dell D600 External Monitor

Created by dave. Last edited by dave, 19 years and 82 days ago. Viewed 12,628 times. #10
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Xorg.0.log.Acer77e (43422)
Xorg.0.log.SonyG400 (52667) (34988)
xorg.conf (2806)

Complaining about Fedora Core 2 on a Dell D600 using an Acer 77e

I have this new Dell D600 laptop which I have installed FC2 on. It has a SXVGA+ (ie, 1400x1050) display. X will display at this resolution (at 24-bit depth) on the LCD display, no problem. However, when I plug the laptop into a docking station which has an Acer 77e 17" monitor attached to it, the Acer displays the 1400x1050 desktop, as viewed through a panning 640x480 window.

Experimentation has shown that the presence or absence of the dock (ie just plugging the Acer straight into the back of the Dell) makes no difference.

I know it is possible to have this monitor display 1400x1050x24 -- Windows does it. I've also driven this monitor at 1600x1280x24 when attached to a different linux system. I also know that it is possible to have this Linux display properly at this resolution on an external monitor -- I have a Sony G400 at the office which does it.

I have gone through the FC2 System Settings -> Display applet and have explicitly defined my monitor as an AcerView 77e. I have confirmed in my /etc/X11/xorg.conf that there is an appropriate monitor defined:

Section "Monitor"
        Identifier   "Monitor0"
        VendorName   "Monitor Vendor"
        ModelName    "Acer 77e"
        HorizSync    30.0 - 72.0
        VertRefresh  50.0 - 120.0
The presence and/or absence of this section doesn't appear to change anything.

When I boot the laptop at the office, it is connected to the Sony G400 and it does the appropriate thing. At home, it still does not behave with the Acer.

In the Xorg.0.log, I've noticed that when connected to the Sony, the log reports:

(II) RADEON(0): Displays Detected: Monitor1--Type 2, Monitor2--Type 1

(II) RADEON(0): Monitor2 EDID data --------------------------- (II) RADEON(0): Manufacturer: SNY Model: 290 Serial#: 8011257 (II) RADEON(0): Year: 2000 Week: 25 (II) RADEON(0): EDID Version: 1.2 [...lots of monitor stuff trimmed...] (II) RADEON(0): End of Monitor2 EDID data -------------------- (II) RADEON(0): (II) RADEON(0): Primary Display == Type 2 (II) RADEON(0): Clone Display == Type 1

...which tells me that it is detecting the Sony all by itself and making appropriate assumptions. Where as when it is connected ot the Acer, I see:
(II) RADEON(0): Displays Detected: Monitor1--Type 2, Monitor2--Type 1

(II) RADEON(0): (II) RADEON(0): Primary Display == Type 2 (II) RADEON(0): Clone Display == Type 1

...which tells me that either the Acer isn't detected at all, or it is detected improperly. However, I still don't know what to do about it. I'm starting to suspect that the config file is merely there for my amusement and xorg is trying to auto-detect things at startup rather than read the config file.

What I can't find is an explanation as to why I'm getting this 640x480 on an external monitor which is clearly capable of displaying much more, nor an explanation of how to fix it. All pages on the web I've found suggest that it means that my monitor can't run the video mode I selected (known to be false) or that my video card can't run the video mode I selected (also known to be false). It has to be a configuration problem.

Incidentally, a co-worker has the same problem, only he's started with FC2 and done an "upgrade" install to FC3.

If you are curious, the xorg.conf file, as well as log files showing what happens when the Acer, Sony, or nothing is plugged into the laptop are attached to this snip (see above, right).

Update, 9 Dec 2004: Opened a bug with >>Xorg and with >>RedHat. The response from Xorg:

------ Additional Comments From  2004-12-08 14:25 -------
the radeon driver defaults to driving each display with a separate crtc (called
clone mdoe).  if it can't find the DDC data for the attached monitor it defaults
to 640x480@60Hz to avoid potentially damaging you monitor.  You can either
disable clone mode (in which case crtc1 will drive both outputs) or add the use
the clonehsync and clonevrefresh options (to tell the driver the monitor's
limits when it can't get DDC data).  see that radeon man page for more about the

------- Additional Comments From 2004-12-08 14:30 ------- for your coworker, in 6.8.x the options have changed a bit, see the radeon man page for more.

I've updated the bug at RedHat.

Update (Mostly Solved), 10 December 2004: So in the FC3 case, the answer is to add lines:

Option      "CRT2HSync" "30.0 - 82.0"
   Option      "CRT2VRefresh" "50.0 - 90.0" the "Device" section describing my radeon device. These values were divined by manually adding the monitor through the Display control panel, and then transfering those values into the Option fields.

As the response from xorg says, consult your "radeon" man page for the equivilent commands in FC2.

In my case it doesn't entirely solve my problem, as the resulting screen has both the left and right sides "wrapped", and no amount of screen resizing will fix that (shrinking the screen shrinks everything, including both wrapped edges). I'll have to play with a modeline probably to get this to work right. Either that or just buy a modern monitor.

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