Hi, I have a Dual-Core Intel Xeon Mac Pro with 2.66Ghz & 4x1 gigs of RAM. 1)I want to upgrade my RAM but I'm not sure where I can get the cheapest ram and if I can install single 2gig, 4gig RAM? 2) I know I have DDR2 FB-DIMM (667Mhz), is it a 240 pin? How do I know how many pins there are? I just updated my OS to Snow Leopard today. Thanks for the help.