Comment 7 for bug 889394

While I agree this may not be an XFPM bug /per se/, it is an XFCE compilation bug in my view since XFPM and xfce4-session both place .desktop files in /etc/xdg/autostart for xfpm and xscreensaver respectively, and both of those apps compete against each other to set dpms settings. I think there needs to be better autodetection in xfpm to see if xscreensaver exists, and disable certain features if xscreensaver provides them.

My machine is a desktop and does not require ACPI-related power management facilities provided by XFPM and so on my machine I simply disable XFPM by removing the .desktop file from /etc/xdg/autostart as I am happy with the screenblanking and DPMS settings offered by xscreensaver alone. But that will not be feasible for laptop computers, for example, that require some mix of features (screenblanking, dpms and ACPI-related power management).