Nouveau and dual-monitor setup in Trisquel 7 (help)

Hi, I'm totally new to Trisquel, and having a hell of a time trying to figure out the display settings. Despite working with a practically-clean install (installed from disk, ran updates, rebooted a few times with no problems), Nouveau isn't working in the slightest.

The GPU is an nVidia GTX 750 Ti, which the system seems to recognize according to lspci:

>01:00.0 VGA compatible controller [0300]: NVIDIA Corporation GM107 [GeForce GTX 750 Ti] [10de:1380] (rev a2)

I made sure the 'xserver-xorg-video-nouveau' package was installed though Synaptic, then edited /etc/X11/xorg.conf to include:

>Section "Device"
>Identifier "nvidia"
>Driver "nouveau"
>EndSection

However, even after rebooting, that didn't work, and I can still only use a single display (as a 'Built-in Display' in 1024x768).

Additionally, a peek into the Xorg.0.log file includes the line:

>(II) NOUVEAU driver Date: Thu Nov 7 14:56:48 2013 +1000

And further down, shows that it loaded the generic VESA driver instead. That seems to indicate that it's trying to use an old version that doesn't support the 750 Ti, even though the latest version was installed through Synaptic.

Ideally, of course, I'd like to use both displays at their native resolutions. Searches for old topics on this matter haven't been very helpful; it seems that most people have no trouble with this, and the above steps work even if they do. What could I be missing?

(Also, apologies for the lack of formatting, but '[code][/code]' doesn't seem to work and I can't guess what the actual tags are.)