There have been several good articles around configuring memory on the mac pro such as this: http://www.diglloyd.com/bike/free/MacPro/memory.html The consensus seems to be that performance is best using 4 sticks of memory of the same size to maximize memory bandwidth and minimize latency (e.g. 4 x 1, 4 x 2, etc.). I am going to order the new Mac Pro with the default 2 x 1 GB configuration. My question is whether I should order 2 x 1 or 2 x 2 from a third party to bring it to either 4 GB or 6 GB. I will be using this machine for home and will likely have the following applications open on a regular basis: PS3, lightroom, safari, firefox, mail, MS word, itunes I will also use the machine for some light video editing and will likely run parallels or something like that for windows XP. I will also run bootcamp with Windows XP for some light gaming. I am concerned whether I will take a performance hit with mismatched memory (2 x 1, 2 x 2) and my gut sense is that 4 GB should be enough, but I cannot stand page-outs. Should I just bite the bullet and get 6 GB?