Hi All, I have Mac Pro 1.1, 2 x 2.66 GHz Dual-Core Intel Xeon. I have 8GB memory, my question is what is the maximum speed memory that I can instal in my mac. The memory for my mac is very expensive, in some cases I read that you can install DDR3 @1066mhz. Which would down speed it to 667mhz. I am fine with it if it works. My question is what is the maximum speed that I can install, what type of Ram can I install, (where to buy it). I am trying to save some money and not to buy 667mhz DDR2. I also read on this forum that people have used 800mhz DDR2, but even that memory is expensive. Can someone please help me.