excerpt of Xorg.0.log

[    15.070] (==) Using system config directory "/usr/share/X11/xorg.conf.d"
[    15.114] (==) ServerLayout "Desktop"
[    15.114] (**) |-->Screen "Screen 2" (2)
[    15.114] (**) |   |-->Monitor "Right screen"
[    15.114] (**) |   |-->Device "Onboard Radeon"
[    15.114] (**) |-->Screen "Screen 0" (1)
[    15.114] (**) |   |-->Monitor "Left screen"
[    15.115] (**) |   |-->Device "PCI nVidia"
[    15.115] (**) |-->Screen "Screen 0" (0)
[    15.115] (**) |   |-->Monitor "Left screen"
[    15.115] (**) |   |-->Device "PCI nVidia"
[    15.115] (==) Automatically adding devices