Monitor input

Hello,

I am trying to connect my laptop to a monitor. The monitor worked fine with my laptop a day ago for weeks, yesterday was a public holiday. after i came to work today, i docked my laptop on the docking station, the extended monitor showed for few mins, then gone.

1: Auto Detect (Analog Input)
Entering Power Save

1: Auto Detect (Analog Input)
In Power Save Mode
Press computer power button
or any key on keyboard or move mouse

Any idea what's going on??
Thanks in advance!