I have a 15" Macbook Pro purchased in 2007. On the Technical Specifications page on the Apple website I find listed what I assume are the speeds and capacities of the internal HD's available at that time *for purchase already installed in the machine*. I haven't been able to find information on what speeds and capacities the machine is *actually capable of supporting*, to know is the most powerful drive I can upgrade to. Thanks for any detailed info, pointers, or recommendations of specific drives (as well as any comments on the difficulties or dangers of replacing the drive).