I recently purchased a iBook 900 w/ Combo Drive and 128MB of RAM, I would like to maximize the amount of RAM in the unit with a 512MB upgrade. But all of the 512MB chips seem to be CAS 3, are there any 512MB chips that are CAS 2? I usually get all of my RAM from Crucial, even though they are usually a bit more expensive, they always have a quality product. Any place actually have a quality CAS 2 chip, or should I just get the CAS 3 chip from Crucial?