Not sure what card I need for my D40 for optimal performance... I want something that will be able to handle the full potential of the camera. (I anticipate doing a lot of rapid shooting. I like to wakeboard so you have to shoot (rapid fire) pretty fast to catch a trick.) Not sure if the buffer in the camera is enough where card speed matters or not... Just looking for some guidance. Oh ya, I am looking for a 4GB card so I can take a bunch of photos at once when I am on vacation. In the meantime I will be using a regular 2GB SD card that is like 133x.