it used to work to make troubleshooting easy, i change to 30 from default 600 xset dpms 30 30 30 xset q ... Screen Saver: prefer blanking: yes allow exposures: yes timeout: 0 cycle: 600 ... DPMS (Energy Star): Standby: 30 Suspend: 30 Off: 30 DPMS is Enabled Monitor is On it doesn't sleep after 30 seconds