Hi, I had purchased a mac book pro. I have more of a debate issue than a problem. I am a student completing undergraduate work and as such I am working on the computer that was bought before coming to undergraduate, 5 years ago (2007 SR MBP). It is running alright as I upgraded the RAM (3 GB) and loaded a new Hard Drive Disk (7200rpm) anywhere in the middle of college. However, the great debate begins in my head (as of 2 years ago): when do I upgrade? So I want to know that how to upgrade the MBP?