I just got a HP EliteBook 8560p with a Mobility Radeon 6470. Installed Ubuntu 12.04 and the binary AMD drivers. In AMD CCC I selected "Single display (Multi-Desktop)" and rebooted. The second display is now completely white and I cant move any windows there. But I can make mouse clicks there and create a new folder...
Then I switched to "Multi-display desktop with display 1": Now the second display is still black and not activated in CCC. I can repeat this forever and nothing changes.
Third thing tried is to generate a dual head config with amd config. Changes nothing to both methods above.
Monitor 1 is a HP LP2475w connected via DVI, the second one is a HP ZR2240w connected via Displayport.
So, how can I use two monitors with AMD cards?