Error when trying dual graphics cards

[Cui, Dexuan]

Hi all,
I have read http://www.x.org/wiki/Development/Documentation/Multiseat, but looks that's mainly for USB graphics card(?) and here I don't use that.

I have a desktop host (HP Compaq 8200 Elite SFF PC) that has an integrated Intel card and an add-on nVidia card.
The "lspci | grep VGA" on the host shows
00:02.0 VGA compatible controller: Intel Corporation 2nd Generation Core Processor Family Integrated Graphics Controller (rev 09)
01:00.0 VGA compatible controller: nVidia Corporation GT218 [NVS 300] (rev a2).

In the default BIOS setting, the integrated Intel card is set to Primary VGA card.
When the BIOS and grub run, only the monitor attached to the integrated Intel card has VGA output.

I tried x86-64 Ubuntu 12.04, RHEL 6.2 and Fedora 17 and it looks Fedora 17 gave the best result, though I still couldn't make both cards work properly -- my goal is something like this: both monitors attached to the 2 card should be able to show a gnome session, or an ever better goal: both monitors belong to a single gnome session.  Is this feasible?

In the x86-64 Fedora 17, the kernel version is 3.3.0-1.fc17.x86_64, and the driver of the integrated Intel card 00:02.0 is i915, and the driver of the add-on Nvidia NVS 300 card is nouveau.

When Fedora 17 just starts up, only the integrated Intel card has VGA output; when the nVidia driver is loaded and X server finishes startup, on the monitor (the first monitor) attached to the integrated Intel card, I see a gnome GUI session and I can log in, but on the monitor(the second monitor) attached to the add-on nVidia card, there is only a Fedora's logo (the small icon with a white f char and blue background) in the center of the monitor -- no gnome session. And the USB mouse/keyboard inputs are routed to the first monitor only and I can't move the mouse cursor into the second monitor.
Please see the attachment for the Xorg.0.log -- looks only 1 monitor is detected and used??? Can you find anything abnormal in the log? -- I don't have much experience about configuring X... :-(
BTW, at this time, "ps aux | grep Xorg" shows:
root       702  0.0  0.1  99352  9648 tty1     Ss+  11:18   0:00 /usr/bin/Xorg :0 -background none -logverbose 7 -auth /var/run/gdm/auth-for-gdm-wSpZLp/database -seat seat0 -nolisten tcp vt1

Later I tried "init 3" to enter runlevel 3 so Xorg was killed.
And I tried "Xorg -configure" to generated a xorg.conf.new and a new /var/log/Xorg.0.log(please see the attached xorg.conf.new and Xorg.0.log.new).
Looks the xorg.conf.new is a good config file: Screen0/Card0/Monitor0 and Scree1/Card1/Monitor1 are defined properly. 
However, when I tried to run "Xorg :0 -config /root/xorg.conf.new", both monitors flicked once and kept black and I got a strange "FATAL: Module fbcon not found" error.
Please see the attached run_Xorg.log and Xorg.0.log.new2 for the details.

Could you please have a look at the logs and see if there is something abnormal? Any suggestion would be appreciated!
If you need any further information, please just let me know.

I'm using X.Org X Server 1.12.0.  It's said one X server can manage two graphics card at the same time? -- if yes, how many gnome session is created, one or two?
It's said people "run dual cards for years" -- do you run one X server or two X servers here?

Thanks!

-- Dexuan


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