I have a desktop with an Intel HD (1x DVI out) and a GeForce GTX 560 TI (2x DVI out) and three monitors. And I would like to use the third monitor with the Intel HD. Xinerama is not what I want. I want all monitors to be different screens (this is the default behaviour for monitors connected to a single graphic card)
When I boot into my Ubuntu live CD (13.10) then Xorg seems to detect all three monitors and Unity uses them as if all monitors were connected to the same graphic card. However the monitor connected to the Intel HD card has a lower resolution. But I guess this is because the drivers aren't completely loaded in the live system.
On my installed system (14.04 LTS) the monitor connected to the Intel HD card remains black and isn't detected by xrandr. Everything I tried in my xorg.conf file didn't work out.
I then created a xorg.conf file in the live system via
X -configure and copied and adapted it (e.g. changed driver names according to the pci adresses) to my installed system. However this led to a black screen on all of my three monitors.
What is wrong with my xorg.conf configuration?
xorg.conf of the live CD
xorg.conf of my current system
xorg.conf that I tried, but it leads to a black screen
$ LANG=C sudo lshw -c video *-display description: VGA compatible controller product: GF114 [GeForce GTX 560 Ti] vendor: NVIDIA Corporation physical id: 0 bus info: pci@0000:01:00.0 version: a1 width: 64 bits clock: 33MHz capabilities: pm msi pciexpress vga_controller bus_master cap_list rom configuration: driver=nvidia latency=0 resources: irq:16 memory:f4000000-f5ffffff memory:e0000000-e7ffffff memory:e8000000-ebffffff ioport:e000(size=128) memory:f6000000-f607ffff *-display description: Display controller product: 2nd Generation Core Processor Family Integrated Graphics Controller vendor: Intel Corporation physical id: 2 bus info: pci@0000:00:02.0 version: 09 width: 64 bits clock: 33MHz capabilities: msi pm bus_master cap_list configuration: driver=i915 latency=0 resources: irq:54 memory:f6400000-f67fffff memory:d0000000-dfffffff ioport:f000(size=64)
By the way:
lspci both list the Intel card as 'Display controller', whereas the Nvidia card is listed as 'VGA compatible controller'. When I switch to the Intel HD card as primary graphics output in the BIOS then
lspci are listing both cards as 'VGA compatible controller'. However then both monitors connected to the nvidia card remain undetected.