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On my desktop I have two partition containing both windows8, one of them is an expired trial. I'm a windows based developer and I want to learn even some Linux development stuff, so I want to install Ubuntu and overwrite that expired Window 8 version. At present when my computer boot there is a dual boot that let me to choose from which win8 start. Can I use the same dual boot to choose between windows and ubuntu? Do I have to remove that dual boot ( don't know how, but will investigate ) before installing Ubuntu? Can I reuse the already present boot manager and must overwrite the useless partition with Ubuntu?