I want screen blanking after 10 or 30 minutes, but at present the screen doesn't blank at all. This has been an issue since upgrading to 11.10. At present, even after a couple of hours, the screen doesn't blank, even though in the screen lock settings it is set to go off after 10 minutes. I can't find any good source of information as to how to troubleshoot the screen blanking / screen saver system in Unity.
Output of gsettings list-recursively | grep "(power sleep-display\|power active)"
(process:3261): GLib-CRITICAL **: g_strv_length: assertion `str_array != NULL' failed (process:3261): GLib-CRITICAL **: g_strv_length: assertion `str_array != NULL' failed org.gnome.settings-daemon.plugins.power active true org.gnome.settings-daemon.plugins.power sleep-display-ac 60 org.gnome.settings-daemon.plugins.power sleep-display-battery 60
For reference, process 3261 is the gsettings process
The machine is a Sony Vaio VPCEB1Z0E, i5-430M, 4GB RAM, AMD graphics