This has probably already been addressed, but tried searching and found nothing. Anyway, my question is this: I've ordered the quad core 2.66GHz model and it will be delivered next week. As I understand it, the computer ships with 4 memory slots, three of which are occupied with 1GB modules. I'm not sure about the triple channel memory though - as I understand it, this means that the computer works best when the memory installed is a multiple of 3, so 3GB, 6GB, 9GB, 12GB etc. But what I am wondering is if you have to install matching memory to get best performance. What I would like to do is remove one of the 1GB sticks which is coming with my Mac Pro and add two 2GB sticks. This would mean that I would have 4 full RAM slots, two with 2GB in and two with 1GB in them, leaving a total of 6GB. The reason I ask is that it is much cheaper to do this than to buy a whole new set of 2GB DIMMs to fill up three slots. Has anyone tried this or know whether it's the best idea?