Hi, I currently own a mac pro 2009 2.6 quad core, can you please tell me which is the best CPU upgrade for this model? Can I buy a board with 2 CPU will it fit/worth the total investment? Is the 6 core 3.33 ghz the best option for this model? I currently have 16 gb ram and I also want to buy a gtx 660 ti from msi, or zotac, can't decided yet.. Are zotac cards noisy when playing games?i don't intend to overlock it. Also want to ask you guys, when and how can I upgrade the efi from 4.1 to 5.1 ? Can you detail me this operation cause I don't find anywhere which a the proper steps which must be followed to upgrade the efi? Do I need to upgrade the efi before install the Ene CPU, or after? Please be kind with me cause I am newbie, this is my first Mac Pro tower, I chooses this because I want to make an good investment for a long time. I expect you relies guys. See you.