the guide on the original page tells you not to update the bios. I would recommend using a separate HD to install this to if it is your first time doing so. When the install is complete, simply choose the disk (using your bios) to boot to. There are other methods out there but I'd recommend this since you won't have to worry about messing up your Windows system... eventually you can find the ways to get around this and install to the same HD without worrying about losing data.

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