So I have my old Macbook Pro back (the 15" 2.33ghz model.) I just recently upgraded the hard drive to a WDC 320GB 7200rpm model and it definitely helped with the performance a lot! However, I popped the ram from my 13" macbook into there (4GB DDR2 667mhz) because I expected that the dual channel benefits would outweigh the 3GB limitation. Strangely enough it will get down to as little as 45mb of free memory when running just safari and mail. (even worse if I'm running aperture or final cut) Does anyone think that could be caused by the 4GB vs 3GB of memory?