Hi. I have an iBook G4 933 mHz that has 384 RAM (custom ordered from Apple store). I desperately want to increase the RAM, to at LEAST 512, if not 640 (which I know is this model's maximum). I also know that there are two RAM slots in it, which, when ordered stock from Apple, have 2 128 MB sticks. So I'm guessing that mine has 1 256 stick and 1 128. This is my first Mac, so I don't really know anything about RAM as far as what is compatible. Are there any good stores you recommend where I can get inexpensive, compatible RAM? Any place you know of with a manual or something on how to install the RAM? Plus, I don't want to void the AppleCare. Or should I just drive 2 hours to my Apple Store and pay out the wazoo? Any help is appreciated!