I have 2 video cards. 1X HD7850 (main video card) 1X HD6450

I have installed the driver for ATI AMD Beta 12.11 from AMD website It works very good..

And than, I go in AMD Catalyst Control to manage my displays. I place them all side by side (4 monitors) They have been detected with the good resolution for each of monitors I have.

Than I reboot without activating Xinerama yet... I see now my 1st video card (HD7850) show the unity bar with wallpaper that's find.

But the other video card(HD6450) show me a white (grey) display on both monitors of the card... If I drag my mouse to one of these monitors, I see a X pointer for my mouse and cant move to a another display anymore.

I reboot... I activate Xinerama, and now I can see all wallpapers on all screens and my mouse can travel where I want. No more white display. Very nice, all monitors working with the good resolution.

But this is when Unity wont start anymore :/ I did unity --replace and I get Warning: no DISPLAY variable set, setting it to :0

(I still can see icons on desktop, move the mouse, right clic and see options from desktop... but no panel bar (unity))

Anyone can help please?

Thank you very much.



Well I did a lot of search and it seems that Unity doesn't work with ATI Drivers for the moment.

So I went to KDE... I have downloaded kUbuntu and installed.

After, I went to terminal by typing Ctrl+Alt+F1 and downloaded the files needed:

sudo apt-get install module-assistant
sudo m-a prepare

I have stopped lightkdm

sudo /etc/init.d/lightdm stop

Than I installed the .run Driver file from ATI. Of course you need to unzip first

unzip filedriver.zip
sudo chmod +x filedriver.run
sudo ./fildriver.run

Follow the installation and answer questions.

And voilà.... you'll have to reboot by doing,

sudo reboot

When you will be back in the desktop... you'll have to configure all your monitors in AMD Catalyst Control Center (admin mode) wich takes few restart to be setup.

For me it's working.

You will also notice that there is AMD Testing use only if you have installed the 12.11 Beta Driver from AMD website.

You can get rid of it by doing this:

sudo gedit /etc/ati/signature

You will see in big letters UNSIGNED. Highlight that and delete it. Now paste this into there:


Save and close that text editor. Now log out of Ubuntu. Log back in. There should be no watermark anymore.

You're done with the installation.

Part of my search is from those website:



Yeah, you will see it is not so funny when mouse is stuck in desktop in another window... you'll have to activate Xinerama to get rid of this.

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