2408 wfp does not enter power saving mode, connected with vga

I'v got a brand new 2408 wfp :smileyhappy:, connected with d-sub/vga at my laptop. This laptop has a nVidia 8600M GT GPU with the latest official nVidia drivers (174.53). I'm also using Windows Vista 32bit.

When I turn off the laptop or when my laptop enters standby or tries to put the monitor in power save, the monitor stays on and responds with a floating box saying "no vga cable".

When I turn the laptop back on or move the mouse the image is comming back.

I really would like that the monitor enters power save mode instead of course.

Does anyone has a solution?

Thanks.