I recently ordered my first Mac Pro, a quad 2.8 off the Apple store refurb section. Spent 3 days loading software, patching Logic Studio, etc, and used it for 2 weeks before deciding I needed 8 cores (my wife wouldn't agree with the word "need" but oh well.) Apple graciously accepted the return and even waived the normal 10% restocking fee, and I ordered a refurb 8-core, which I just received. Can I simply move the boot drive over and take advantage of the new cores? Or is there a requirement to start with a fresh drive so it can "build" itself for 8 cores. I don't want to move the drive only to find it senses a major hardware change and refuses to boot or worse, becomes unuseable in the original 4 core so I cannot use the Migration Assistant, although I have a Time Machine backup so all is not lost. Anyway, hoping a 2 minute drive/RAM swapping exercise is all that is required... anyone have experience with this?