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I am new to Linux. I am sure if I searched enough I could figure this out but, I keep running into the same issue. I have just recently installed Ubuntu 12.04 LTS. I unfortunately have only one computer in working order in my household. My computer has three 500GB hard drives, and I have a different OS installed on each hard drive: Windows XP, Windows 8 and Ubuntu 12.04.
I am asking how do I load a boot menu screen immediately after POST automatically. I have found resources to do this from a Live USB, but I'm looking for an easy way to select my operating system from a boot menu.