text: If you have an RGB port on the back you and "share" your desktop with an external monitor (mirrioring the desktop on both).  However if you need to extend (have your desktop use both monitors as one deskotp environment) with a laptop then you have to invest in an external box.  However your cipset might (and I emphasise might) be able to support dual monitor sharing.  Plug an external monitor into the port on the back and go to Display Properties and see if you have the option there to "extend Desktop".  If  you  do then the chipset supports it.  If not you can use a hardware solution like this (http://www.matrox.com/graphics/offhome/dh2go/home.cfm)\n\nHope that helps.