I have no clue how external monitors work. However, I am planning to hook up an external LCD monitor to my 12'' Rev D powerbook. My question is, can I hook up a 24'' Dell 2407WFP? Am I going to notice a decrease in performance by using an external monitor? I know you need a bigger graphics card to power something like the 30'' cinema display, but I don't know how that really works. If I run something graphics intensive, like a game, is it going to run slower with an external monitor hooked up as opposed to on the smaller screen, because the graphics card is being used to run the external monitor? Again, I really have no idea how this works, or even if the 12'' powerbook can work with the 2407WFP, so any help would be appreciated.