Ubuntu 12.04 Dual Monitors Not Working

[N00b4Now]

Hello All,
It is my first posting, please let me know what I can do to improve my presentation skill.


My issue is getting Dual Monitor working under Ubuntu 12.04. I have just upgraded to the AMD Video Driver for Ubuntu (amd-driver-installer-12-4-x86.x86_64) and when I tried to have Multi Desktop setup with two monitors, the 2nd monitor shows a white screen with black X as the cursor.


Would you please helping me solving this issue?

Please find the attached xorg.conf for my current duo monitor setup.


Thank you very much for your help,


Noob4Now

[cortman]

Hi, what's the output of


xrandr

with the second monitor plugged in?

[N00b4Now]

Hello Cortman,
The output of xrandr is the following:
************************************************** *******************************************
Screen 0: minimum 320 x 200, current 1920 x 1080, maximum 1920 x 1920
DFP1 disconnected (normal left inverted right x axis y axis)
DFP2 connected 1920x1080+0+0 (normal left inverted right x axis y axis) 509mm x 286mm
1920x1080 60.0*+
1680x1050 60.0
1400x1050 60.0
1600x900 60.0
1360x1024 60.0
1280x1024 75.0 60.0
1440x900 60.0
1280x960 75.0 60.0
1152x864 60.0 75.0
1280x768 75.0 60.0
1280x720 75.0 60.0
1024x768 75.0 60.0
800x600 75.0 60.3
640x480 75.0 59.9
CRT1 disconnected (normal left inverted right x axis y axis)
CRT2 disconnected (normal left inverted right x axis y axis)
************************************************** ******************************

The 2nd LCD monitor is showing white screen with black cursor when I did xrandr.

Thank you for your time,

N00b4Now

[cortman]

Have you been setting the dual monitors with the Catalyst Control center?
If so, and it still isn't working, you may want to try the open source driver instead- I quote-


This driver is not as fast as the closed-source, proprietary "fglrx" driver from AMD/ATI Inc. for some cards, but has better dual-head support, and supports some older chipsets that fglrx does not.

See here (https://help.ubuntu.com/community/RadeonDriver) for open source driver details.

[scottbomb]

This might also help:


http://ubuntuforums.org/showthread.php?t=1965529

[N00b4Now]

Thank you all for the quick responses. I tried all the suggestion and no resolution.

I ended up enabling the CrossFireX functionality of the GPUs and Enable Tear Free Desktop to make the dual monitor work.

In Windows 7, I usually don't activate CrossFireX when I am not gaming and the old habit does not work in Ubuntu 12.04.

Now all is well, I learn something new today.

Thank you again for your help and have a nice day.

N00b4Now.

[houston schmitt]

This worked for me (after 12.04 Ubuntu install) and may be a simpler solution. The install had found an ATI/AMD proprietary FGKRX graphics driver and installed it. When I deactivated it (system settings...hardware...additional drivers) , I was able to get the dual displays to work through the Displays program. It appears that the generic driver for 12.04 works just fine and the proprietary driver does drive dual monitors correctly.

(Caveat: I am not a linux expert)