Every time I boot up into Ubuntu 12.04 Unity. There is no screensaver. It just goes dark after a preset duration.
I believe I had to install the xscreensaver from Synaptic, which I also had to install.

The problem with the screensaver not starting up at boot may have something to do with this error message I get when I go to System Settings > Preferences > Screensaver.
I get this pop up box with this error message:
The XScreenSaver daemon doesn't seem to be running
on display ":0".  Launch it now?
Cancel or OK
When I click OK everything works as expected until I logout again.
I have only one monitor. I installed the NVIDIA (post-release updates) (version current-updates) version 295.49 from Additional Drivers.

Any ideas?