So, I am using C3-10600 (1333MHz) DDR3 204-pin SO-DIMM RAM - 4GB in 2 slots. Q1. Can I extend my RAM such that I have the following setup: 2 + 2 + 4 + 4 = 12GB RAM, utilizing all 4 slots. Q2. Can I buy the RAM off of ebay? I live in the UK; some one suggest me how to buy this RAM. I have never upgraded/opened my mac ever. Kinda newbie in assembling tinkering with computers.