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My first time trying to use Ubuntu. I clean installed the Ubuntu 12.10-beta2 on an old Dell Dimension 4600 today. Install seemed to go fine, but after restarting and entering the requested passwords I'm taken to a purple screen with no panels, launchers or anything else--just a purple screen. I'm able to access the terminal from the screen with ctrl-alt-t, but I'm not sure at this point in my Linux training how to search for errors. Also have no Internet connection (I'm typing this on a mac), but I'll have to deal with that later. Would appreciate any suggestions.