I just upgraded my MBP ram from 2gb to 3 gb and everything seems OK. Two, probably stupid, questions: 1.- How can I be sure that everything is fine? Is there a way to check ram using Mac OS X? Do I need to download a specific program to do that? 2.- I have been using my laptop all morning. I can see the performance improvement when using several applications at the same time and my page in/page out ratio decrease a lot. However, when using basic applications (safari, mail, etc.), I notice I have little free memory. Is this normal? is the system supposed to take as much memory as it can weather it really is needed or not? How does it work?