How to connect a projector to a FreeBSD laptop?

[Unga]

Hi all

I have a laptop running FreeBSD 8.1 with X server 1.7.5.

I need to connect a projector to this laptop to show a presentation.

After connect the projector to the laptop, I had rebooted the laptop, the projector's screen just blink only.

Could somebody please highlight to me how to successfully connect a projector and what configurations needs to be done?

Many thanks in advance.

Unga