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UQ-igor

Member

Registered: 2009-03-05

Posts: 42

[SOLVED] ATI, radeonhd, xrandr dual screen setup trouble

Hi fellow archers,

I'm trying to configure an external monitor on my Thinkpad T60p. Relevant Information:

└─[~]$ lspci | grep ATI                                                                                                                                [T60p]-[21:32]-[Tue Aug 11]
01:00.0 VGA compatible controller: ATI Technologies Inc M56GL [Mobility FireGL V5200]

I want to run the laptop screen at native resolution of 1400x1050 and the external monitor at 1280x1024 if possible.

xrandr --output VGA_1 --auto --left-of PANEL 
xrandr -q
Screen 0: minimum 320 x 200, current 2464 x 900, maximum 2840 x 1050
VGA_1 connected 1440x900+0+0 (normal left inverted right x axis y axis) 408mm x 255mm
   1440x900       59.9*+   74.9  
   1280x1024      75.9     75.0     71.9     59.9  
   1152x864       75.0     74.9  
   1024x768       75.1     70.1     60.0  
   832x624        74.6  
   800x600        72.2     75.0     60.3  
   640x480        75.0     72.8     66.7     60.0  
   720x400        70.1  
   640x350        70.1  
PANEL connected 1024x768+1440+0 (normal left inverted right x axis y axis) 286mm x 214mm
   1400x1050      60.0 +
   1680x1050Scaled   60.3  
   1400x1050Scaled   60.3  
   1440x960Scaled   60.4  
   1280x1024Scaled   60.5  
   1280x960Scaled   60.4  
   1280x854Scaled   60.4  
   1280x720Scaled   60.4  
   1152x768Scaled   60.3  
   1024x768Scaled   60.4* 
   800x600Scaled   60.3  
   768x576Scaled   60.4  
   854x480Scaled   59.8  
   720x480Scaled   59.8  
   640x480Scaled   60.1  
   320x240Scaled   57.6  
   320x200Scaled   55.7  
DVI-D_1 disconnected (normal left inverted right x axis y axis)

This turns the external monitor on and displays a resolution of 1440x900 which is fine, but it changes the laptop monitor resolution to 1024x768 which is NOT fine because it looks nasty. So I tried:

xrandr --output PANEL --mode 1400X1050 --pos 0x0 --output VGA_1 --mode 1280x1024 --pos 1400x0                                      
xrandr: cannot find mode 1400X1050

Really? But you just told me that mode is available!

Whats going on here and is there anyway to get a usable dual screen setup? I need the laptop screen to be at 1400x1050 (native res) because any other res looks pretty bad on the laptop. The external monitor can be at any decent resolution (1440x900, 1280x1024...).

Thanks for any help!
Regards,
-Igor

Last edited by UQ-igor (2009-08-12 04:59:48)

flamelab

Member

From: Athens, Hellas (Greece)

Registered: 2007-12-26

Posts: 2,160

Re: [SOLVED] ATI, radeonhd, xrandr dual screen setup trouble

Have you tried with xf86-video-ati-git as well ?

UQ-igor

Member

Registered: 2009-03-05

Posts: 42

Re: [SOLVED] ATI, radeonhd, xrandr dual screen setup trouble

Thanks for replying flamelab,

It seems that this solved the problem. After switching to xf86-video-ati (not git), I'm able to get the right resolutions on both monitors. I'm using a friends monitor for testing at the moment. Hopefully, when I go and buy a monitor tomorrow, I'll be able to get xrandr to play nice with as well, otherwose I'll end up with a rather expensive doorstop.

Cheers again for help!
-Igor

UQ-igor

Member

Registered: 2009-03-05

Posts: 42

Re: [SOLVED] ATI, radeonhd, xrandr dual screen setup trouble

So I went and got me a 22" external monitor, but xrandr lets me run it on maximum resolution of 1280x1024 instead of at 1680x1050.

└─[~]$ xrandr -q                                                                                                                   [T60p]-[12:41]-[Wed Aug 12]
Screen 0: minimum 320 x 200, current 1280 x 960, maximum 1400 x 2074
VGA-0 connected 1280x960+0+0 (normal left inverted right x axis y axis) 473mm x 296mm
   1280x1024      75.0     60.0  
   1280x960       60.0* 
   1152x864       75.0  
   1024x768       75.0     70.1     60.0  
   832x624        74.6  
   800x600        72.2     75.0     60.3     56.2  
   640x480        75.0     72.8     66.7     59.9  
   720x400        70.1  
LVDS connected 1280x960+0+0 (normal left inverted right x axis y axis) 286mm x 214mm
   1400x1050      60.0 +   50.0  
   1280x1024      59.9     60.0  
   1280x960       59.9* 
   1280x854       59.9  
   1280x800       59.8  
   1280x720       59.9  
   1152x768       59.8  
   1024x768       60.0     59.9  
   800x600        60.3     59.9  
   640x480        59.9     59.4  
DVI-0 disconnected (normal left inverted right x axis y axis)

As you can see, no resolutions higher than 1280x1024 are reported for the external monitor. How can I force xrandr to set a resolution of 1680x1050 on the external monitor? This is with xf86-video-ati driver. xf86-video-radeonhd gives even worse results - reports max res of external monitor to be 1024x768.

Thanks for any suggestions,
Igor

UQ-igor

Member

Registered: 2009-03-05

Posts: 42

Re: [SOLVED] ATI, radeonhd, xrandr dual screen setup trouble

All right, got it all running nice.

Here is what I had to do to get xrandr to play nice.

First, find out the proper modeline for the mode you need. In this example I have a 19" monitor with highest res 1440x900 which was NOT being reported by xrandr. So:

$ cvt 1440 900
# 1440x900 59.89 Hz (CVT 1.30MA) hsync: 55.93 kHz; pclk: 106.50 MHz
Modeline "1440x900_60.00"  106.50  1440 1528 1672 1904  900 903 909 934 -hsync +vsync

Let xrandr know about this modeline

xrandr --newmode "1440x900" 106.50  1440 1528 1672 1904  900 903 909 934 -hsync +vsync

add mode for VGA-0 display

xrandr --addmode VGA-0 1440x900

Setup the screen

xrandr --output VGA-0 --mode 1440x900 --above LVDS

I have the external monitor above my laptop, hence the --above line

If you get an error about screen dimensions too big, you need to add a "Virtual dimension" line to xorg.conf

I'm using xf86-video-ati-git drivers
Hope that helps if anyone has the same problems
Cheers,
-Igor