I have killed gnome-screensaver process and was able to reproduce this issue.
I don't know whether this is relevant, but "xset q" shows DPMS (Energy Star): Standby: 600 Suspend: 600 Off: 600 DPMS is Enabled Monitor is On
For any value in settings. Most likely something fails to adjust DPMS.
I have killed gnome-screensaver process and was able to reproduce this issue.
I don't know whether this is relevant, but "xset q" shows
DPMS (Energy Star):
Standby: 600 Suspend: 600 Off: 600
DPMS is Enabled
Monitor is On
For any value in settings. Most likely something fails to adjust DPMS.