monitor power management doesn't seem to work

Hi There,

I got OSS11 with KDE 4.1 going here and I have setup settings with KPowersave. I have set my screen to turn off after 10 Minutes and checked the checkmark saying “Enable specific display power management” but the screen never turns off and it for sure should support this. It’s an Acer AL2216W. What am I doing wrongly or do I have to take a different approach in order to get my screen switching off after a certain time of inactivity?