Updating the system will solve this issue. I would recommend activating the Proposed repositories in case you have not yet done so, but after upgrading 12.10 that minor bug should be fixed. Is not an error, nor does it mean you are not using the drivers correctly.
The bug is simply that the Window, in that line stops mentioning the correct video card. This does not affect the performance, 3D effects or anything else graphics related if that is what is making you doubt.
Here is 12.10 after upgrading and using the 313 drivers as you are doing right now:
And this one
Also in the Software Sources I have all updates active:
So with that in mind, do an update and done. Even if you still see that text not showing the video card, it is just that, a text that is not showing the video card. The video card will still work fine (I know it scares me when I did not see it detected there the first time).
UPDATE - Just did an awesome check with Synaptic and Aptitude to find what did I do apart from the mentioned stuff above. The only thing I found that involved video cards was installing the mesa utils because I normally tend to use the glx commands to check stuff out and to run the
sudo nvidia-xconfig command to create the
xorg.conf file only if I got an Nvidia missing configuration file bug. Maybe you can give it a go:
sudo apt-get install mesa-utils
and restart the session or reboot. Apart from this, we would end with the same configuration for everything.