I'm using a Late 2011 13" MacBook Pro with an Intel i5 @ 2.4 GHz and 4 GB 1333 MHz ram. The computer has started to get older. I was going to upgrade the ram but since Mavericks come out, the ram problem just went away and now, it started to get slower and slower. So I was thinking of upgrading my ram to at least 8GB and my CPU. I have two question about that. As I have 1333Mhz rams installed by default, the motherboard should not support 1666Mhz rams. But can I use 1666 Mhz ones and if I can will it make any difference? Also is it possible to upgrade the CPU of my computer? If yes how can I find a CPU compatible with the other components?