Screen stopped blanking

[Matthew Saltzman]

I have a Dell Latitude E6410 with an nVidia graphics card, using the
nouveau driver and the GNOME desktop on F17.

Recently, the laptop screen stopped blanking when idle in X mode.  I've
modified the screen-blank settings, to no avail.  If I switch to a
virtual console, blanking works fine.  It's possible that the change
occurred with a kernel update or an X update, but the nouveau driver
hasn't been updated since June.

Any hints what might have changed or what I might look for to get it
working again?

TIA.

-- 
Matthew Saltzman
Clemson University Math Sciences
mjs AT clemson DOT edu