eep:
I see JD is helping you in the other thread. I wouldn't deviate from that direction. I am just posting this in case it helps JD or someone else isolate the root cause.
The Xorg.0.log you posted was using xorg.conf.new so doesn't tell us what the system is "calling" the output ports detected. (I haven't figured out a better way to find them yet.) However, it is possible that your issue is similar to my G5 in that it "sees" multiple heads and tries to assign multiple drivers to multiple cards as seen in this section from your upload:
Code:
"...
/usr/share/X11/xorg.conf.d"
[ 52.510] (==) ServerLayout "X.org Configured"
[ 52.510] (**) |-->Screen "Screen0" (0)
[ 52.510] (**) | |-->Monitor "Monitor0"
[ 52.511] (**) | |-->Device "Card0"
[ 52.511] (**) |-->Screen "Screen1" (1)
[ 52.512] (**) | |-->Monitor "Monitor1"
[ 52.513] (**) | |-->Device "Card1"
...
[ 52.621] (**) FBDEV(0): claimed PCI slot 0@0:16:0
[ 52.621] (II) FBDEV(0): using default device
...
dmesg appears to indicate your display detected properly but may be getting assigned to "Monitor1" instead of "Monitor0"
Code:
...
[ 0.759985] nvidiafb: Device ID: 10de0110
[ 1.002997] nvidiafb: EDID found from BUS1
[ 1.102642] i2c i2c-1: unable to read EDID block.
[ 1.254636] i2c i2c-1: unable to read EDID block.
[ 1.406634] i2c i2c-1: unable to read EDID block.
[ 1.459001] nvidiafb: Found OF EDID for head 2
[ 1.459009] nvidiafb: EDID found from BUS2
[ 1.459039] nvidiafb: CRTC 1 is currently programmed for DFP
[ 1.459059] nvidiafb: Using DFP on CRTC 1
[ 1.459078] nvidiafb: Panel size is 1024 x 768
[ 1.459095] nvidiafb: Panel is TMDS
[ 1.460091] nvidia: Backlight initialized (nvidiabl0)
[ 1.460595] nvidiafb: Flat panel dithering disabled
[ 1.463396] Console: switching to colour frame buffer device 128x48
[ 1.465963] nvidiafb: PCI nVidia NV11 framebuffer (32MB @ 0x98000000)
...
Again, I wouldn't deviate from JD's instruction in the other thread. There is no reason NV with xorg.conf and KMS disabled shouldn't work for you. (That I know of, but I don't know much.

)