So ram prices have finally come down and I want to load up my 2009 8-core mac pro. It currently has 6x1GB, with 3 sticks in each riser. I've been browsing different configurations on OWC and am sort of confused how some of them work. One configuration, for example is 3x4GB for 12GB total. Since this setup is only 3 sticks, if I removed all of the sticks currently in the computer and put all three of those in one of the risers and left the other riser empty, will the machine run? If I did purchase this setup, could I put the 3x4GB sticks in one riser, put one of the existing 1GB sticks in the 4th slot on that riser, and then fill the second riser with 4 of the 1GB sticks? I know there are differences between triple/dual channel, but I haven't seen whether the stick configuration in the two risers has to be identical... Thanks!