We have a laptop at work that won't work with an external display in a specific situation.

If the laptop is started up prior to being placed on its dock/port replicator, the external monitor that is connected to the dock won't activate. If I press fn+f8 to change displays, nothing happens. If I try to extend the display to the external monitor in the display settings, nothing happens. If I take the computer off of the dock and put it back on, nothing happens. The mouse and keyboard connected to the dock do function when the computer is on the dock. If the computer is restarted and boots up while on the dock, then the external display works fine.

The laptop is a Dell Latitude D830. The monitor is being attached via a DVI cable to the dock.