Hi at all! I'm going to upgrade the ram of my Macbook white late 2007. Now I have 4GB (2x2GB) and I would like to have 6GB. I know that my Macbook can recognize 6GB only if I use a ram of 2GB and another of4GB. Do you suggest me a brand? I've seen a Crucial 4GB DDR2 SDRAM 667MHz. What do you think?