Sorry in advance for not provide the specifics on my model, but I have a white Macbook 13.3" that was manufactured in 2007. After running my serial number through powerbookmedic.com, I found that my model's max RAM is 2 GB. Here are my quesitons: 1. I'm going to buy two 1GB sticks to replace the RAm I have now. Is it safe to exceed the 2GB limit and insert two 2GB sticks? 2. Is there a specific type of RAM that I should make sure I have? What is the difference between DDR2 and DDR3, and does it relate to my model? Thanks for the help.