I'm sure there are multiple threads started but for the life of me I can't find anything. I should be receiving my new Imac with 3TB Fusion next week. Right now I have an 2009 Imac with about 500GB of data on the internal storage, and another 900GB on an external drive. Some questions I have about transferring Should I update the 2009 to Yosemite? Will it make a difference if the two computers are different OSX? What is the physical way to do this? Do I plug an Ethernet cable between the two? Since my storage use now is larger than the 09 can handle and I dont have enough space on the external for everything, am I in trouble not backing up? Is it better to just open the new computer out of the box and move over data files/download software as needed? Im afraid moving the current set up over is going to import a lot of junk like DVD software etc. My wife has photos all over the place combined between Iphoto and Lightroom and Photoshop. Does anyone know where I can source all the files for sure so nothing is missed on the transfer? If you know of threads that you can point to that answer any of these questions, I apologize for not finding but could you please link Much appreciated.