Well I ordered 4GB ram from OWC (first time buyer and first time mac owner). I installed them and my MBP would not start up. A screen kept coming up to tell me to restart. So, put in the apple ram, and everything was ok. Tried the OWC a 2nd time....no good. Put the apple ram in and back to normal. Has anyone else had this type of problem? I'm gonna return the ram, this is my first Mac, i'm scared to death that i'll mess it up. I think i'll go with Crucial Ram, that the next best thing? Unless someone can tell me what i did wrong. I just cant think of anything other than them not snapping in well like the Apple ram.