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Bogart

Member

From: Madrid, Spain

Registered: 2005-06-22

Posts: 272

xf86-video-intel problems (resolution, DRI) [SOLVED]

I updated to day the xf86-video-i810 to the new *-intel driver and I encountered 2 problems. I have an old 845G card and an old CRT monitor that I use at 1024x786.

Problem 1: Incorrect resolution

The new native modesettings automatically reads the DCC from your monitor for the different modes and ignores your xorg.conf settings. So I ended up with a 1360x768 resolution and couldn't change it. The solution is to edit your /etc/X11/xorg.conf file adding the following:

Section "Monitor"
    Identifier  "My Monitor"
    HorizSync   30-70
    VertRefresh 50-120
    Option    "DPMS"
    Modeline  "1024x768" 86.18 1024 1088 1200 1376 768 769 772 803  -HSync +Vsync
    Option    "PreferredMode" "1024x768"
EndSection

Section "Device"
    Identifier  "** Intel i810 (generic)               [i810]"
    Driver      "intel"
    Option  "Monitor-VGA"  "My Monitor"
EndSection

Note that the two important lines I added were the Option "PreferredMode" "1024x768" to the "Monitor" section and the Option "Monitor-VGA" "My Monitor" to the "Device" section. If you're using a laptop you might need to use "Monitor-LVDS" instead of VGA, and if you're using DVI I'm not sure, but you can check your /var/log/Xorg.0.log to find how's your video output called.

This way I forced the driver to use my settings.

Problem 2: no DRI

I also had no DRI after the upgrade (you can check it with the command "glxinfo | grep rendering"). Looking at /var/log/Xorg.0.log I found that it complained of not having enough memory for enabling it, and in the previous lines it said it was allocating something like 6000 lines for pixmap chache, so I thought that was the problem. I added an Option "CacheLines" "768" to the device section and with that it left enough memory for DRI (note that 768 is my resolution height (1024x768).

Section "Device"
    Identifier  "** Intel i810 (generic)               [i810]"
    Driver      "intel"
    Option  "Monitor-VGA"  "My Monitor"
    Option "CacheLines" "768"
EndSection

Now everything works fine (Xv video, DRI). Performance is even a bit better when using Beryl or GoogleEarth (get a bit more fps in glxgears), and I didn't find any instability so far.

EDIT:
Another thing: Changing resolution crashed the server. This got solved by using the xorg-server-1.3 that supports xrandr. Now all works good, except that the KDE utility to change resolution has no effect. But it can be changed with the command "xrandr -s 1280x1024 -r 60" where -s is the size and -r the refresh rate.

Last edited by Bogart (2007-05-20 20:31:06)