I am running the Demo version of Ubuntu 12. I have dual displays on 2.2GHz dual core Intel cpu with 4gbs of RAM. The demo recognizes the dual displays and correctly identifies each one (Diff. manufacturers). I am unable to reorient the displays, when I move the location on the setup screen so as to place the display that should be to left the action looks OK on the screen but when I select "Apply" the result is unpredictable i.e
The system mostly either locks up or both displays go black and the system also locks up. Ctr-Alt_Del does not work. I have to hit the reset button on my hardware to start all over again. I have occasionally had the system actual do what it should do and I am then able to slide my cursor across from the left to the right display as it should.