Hi everyone, I've got this MacBook 4,1 from 2008 that I've been thinking of upgrading it's RAM, in order to make better use of it. Right now it's using its two (1GB each) factory chips with which it came with. Because I don't know that much about computers, could someone clarify if the upgrade I'm planning to do will need to be on both sockets? i.e.: If I'm aiming to upgrade to 4GB, should I replace both chips with one 2GB chip each? Or could I buy one 4GB chip, and only replace one chip and leave the other one as it is? Because GarageBand, Photoshop and iMovie (720p/1080p projects usually) is my main concern, what is your advice on the upgrade which will serve my needs best, while keeping in mind the cost involved with it? Thank you in advance for your time. Any insight is much appreciated.