I am looking to purchase a MacPro4,1 8-core 2x2.93GHz, and do the firmware hack to 5,1, so it can accommodate the 1333MHz memory. I'm buying this machine for virtualization, so I will be looking to upgrade the memory to 48GB, with possible future growth. What are the configurations on this setup that will recognize and support 1333MHz RAM? Is it possible to plug to use a 3x16 configuration (versus 6x8), so as to allow for future expansion while still running at 1333GHz? If I do populate it with a 6x8 configuration, are there configurations that will support growth at 1333MHz? Lastly, do the 16 GB DIMMs work in triple channel configurations? I though I read something about them being dual channel. Thanks in advance!