Hello. At present, I know that I need at least 6GB. I may end up installing 8, 12 or 16GB in 1-2 months. I don't expect that I will use more than 16GB within a year. Taking the increase in dual-channel performance into consideration, could you please advice on which RAM configurations to buy? I know that the MacPro comes with 2GB standard and there are totally 8 slots. I am not sure how the RAM are arranged. Given the cost, I will buy from third parties rather than from Apple. Thanks.