nVidia Series 8, Dual-Head, 2 X screens, KDE4, randr see one display
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nVidia Series 8, Dual-Head, 2 X screens, KDE4, randr see one display
As in subject.
I have two Monitors, 2 X screens, GeForce 8800GTS.
Both screen have different resolutions. My CRT (CRT-1) is 1600x1200 by default (that is what I want), my TV is LCD, so I want to use native resolution, which is 1680x1050 and I am using it. The problem is XRandR see only one display and, because of that KDE4 is setting plasma to 1600x1200 for TV. I need to make XRandR see both displays normaly. It see one display and two screens.
If you are using the Nvidia driver, I believe that the Nvidia utility program "nvidia-xconfig" replaces most of the functions of "xrandr", making them invalid. See the README for how to proceed with using "nvidia-xconfig"
The point is I almost can recite nVidia How-To and I do not use automatic tools for configuration. Anyway just for sake of my curiosity I tried it out - it gave me same config as have!
I thought that this would be useful, from man/1/nvidia-xconfig.
Quote:
--separate-x-screens, --no-separate-x-screens
A GPU that supports multiple simultaneous display devices can either drive these display devices in TwinView, or as separate X screens. When the '--separate-x-screens' option is specified, each GPU on which an X screen is currently configured will be updated to have two X screens configured. The '--no-separate-x-screens' option will remove the second configured X screen on each GPU. Please see the NVIDIA README description of "Separate X Screens on One GPU" for further details.
The last reference is to Chapter 15 in the README.
Am I correct in assuming that you are stuck in TwinView? This seems a way out.
Last edited by thorkelljarl; 05-21-2011 at 01:48 AM.
On one side side I really like TwinView, cause I am able to move windows without any problem. On the other side its not exactly what I want. I have 3 configurations:
1. 1 screen, 1 display, 1 monitor
2. TwinView, 2 displays, 2 monitors, 1 screen
3. 2 screens, 2 monitors, one screen in randr?
Separate screens aren't good at all. I get plasma-desktop on second screen with same resolution as on first, where:
1 screen: 1600x1200 4:3 monitor
2 screen: 1680x1050 16:10 tv
I don't know if you've solved your xrandr problem; if not, you need to use the -d option.
I have a setup with two identical monitors as two X screens, :0.0 and :0.1. Here's what xrandr looks like:
Code:
root@gaz:~# xrandr
Screen 1: minimum 320 x 200, current 1280 x 1024, maximum 4096 x 4096
VGA-1 connected 1280x1024+0+0 (normal left inverted right x axis y axis) 338mm x 270mm
1280x1024 60.0*+ 75.0
1152x864 75.0
1024x768 75.1 60.0
800x600 75.0 60.3
640x480 75.0 60.0
720x400 70.1
root@gaz:~# xrandr -d :0.0
Screen 0: minimum 320 x 200, current 1280 x 1024, maximum 4096 x 4096
DVI-I-1 connected 1280x1024+0+0 (normal left inverted right x axis y axis) 338mm x 270mm
1280x1024 60.0*+ 75.0
1152x864 75.0
1024x768 75.1 60.0
800x600 75.0 60.3
640x480 75.0 60.0
720x400 70.1
root@gaz:~# xrandr -d :0.1
Screen 1: minimum 320 x 200, current 1280 x 1024, maximum 4096 x 4096
VGA-1 connected 1280x1024+0+0 (normal left inverted right x axis y axis) 338mm x 270mm
1280x1024 60.0*+ 75.0
1152x864 75.0
1024x768 75.1 60.0
800x600 75.0 60.3
640x480 75.0 60.0
720x400 70.1
root@gaz:~#
The reason that xrandr with no arguments defaulted to Screen 1 is that I ran it from a terminal opened on Screen 1, so the terminal's DISPLAY contains :0.1. Had I run it from a terminal opened on Screen 0 DISPLAY would have been :0.0 and xrandr would have shown the status of Screen 0.
Last edited by jamesf; 12-30-2011 at 08:06 PM.
Reason: clarification
Before you give up entirely consider using a WM/DE that doesn't take such firm control of your system.
KDE4 gave me no end of problems setting up my graphics because it wanted to re-apply so much of my configuration, especially in the early KDE4 releases.
Try a lighter window manager, something like XFCE (which has worked quite well for me in the past) or fluxbox that doesn't want such an iron grip on your display configuration.
Note that all of this post is opinion. The only real fact is that I had a much easier time specifying unusual X configurations, including TVs, when using a WM/DE other than KDE4. Perhaps my difficulties were the result of my own stupidity; perhaps not.
Most of my TV successes were with very different resolutions. To get readable text on the TV required quite different settings than on the monitor. I only pointed out that my monitors happened to be identical to avoid confusion, not because it is any sort of requirement.
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