X w/ "nvidia" fails to start on Geforce 8800 GTS

Michael:
There's not quite enough information here to diagnose your problem. nvidia-glx (which corresponds to the 96xx drivers) will not work with your card (due to your cards newness - see https://help.ubuntu.com/community/BinaryDriverHowto/Nvidia ). In theory nvidia-glx-new should work but you may be running into a known issue. Can you please attach the your
/var/log/Xorg.0.log
file that is produced directly after using the nvidia-glx-new driver (you may need to reboot to ensure you are using this 100 series driver) with nvidia in your xorg.conf?

You're right, the nvidia-glx/96xx driver is too old. I enabled "nvidia" support via the restricted drivers manager, and then used synaptic to switch from nvidia-glx to nvidia-glx-new with the latest versions of gutsy. Still, the same error comes up. Here is the Xorg.0.log

Michael:
Could you also attach the dmesg.txt file produced after starting X when running
dmesg > dmesg.txt
?

Here you go. I did this from recovery mode to avoid trouble with failsafe X.

Michael:
Your dmesg shows your system is trying to use the nvidia-glx driver:
[ 43.668831] NVRM: loading NVIDIA Linux x86_64 Kernel Module 1.0-9639 Mon Apr 16 20:18:26 PDT 2007
rather than nvidia-glx-new. Can you use apt to remove nvidia-glx and then use apt to install nvidia-glx-new and repeat the dmesg test please?

Alright. It works now.

I am 99% certain that previously I had nvidia-glx-new only and X still failed to start. Maybe that was because of a bug that was fixed.

Thank you for your assistance.

Michael:
You're welcome but I didn't do anything! Your problem could well have been due to Bug #98641 which is in the process of being (or may recently have been) fixed. It's hard to say without the log of when it was broken but I'll resolve this particular bug as Invalid as you say you are no longer seeing the issue now.