Sony PCG-812 - Manual (Page 70)

To remove your computer from the docking station when the power is off
1 Turn off your computer and the connected peripherals.
2 Slide the docking lever forward into the release position to disengage
the computer from the docking station.
3 Lift the computer away from the docking station.
4 Close the docking station port cover on the back of your computer.
If the docking station lever does not move, insert a thin, pointed object into the manual
eject hole on the rear of the docking station.
VAIO Notebook Computer User Guide