How to Configure BIOS for Dual Boot
Your BIOS is the most basic operating system on your computer, which means that it must be "on the same page" with all major system setup changes lest they fail or exhibit unwanted characteristics. Setting up your computer to "dual boot" means placing two operating systems on separate partitions of the hard drive. This means you will have to set up certain options in your BIOS as well to ensure that they are recognized.
Reboot your computer and press the designated key (as listed in the start-up messages, which appear onscreen) to enter your BIOS. This key is typically either "Esc" or one of the "F" keys.
Navigate to the "Boot" menu of your BIOS, using the arrow keys.
Scroll to the option for "First Boot Device" by using the arrow keys. Press "Enter" to bring up a list of available options. Choose the option for your "HDD" (hard drive) and press "Enter" to confirm.
Navigate to the option for your second, third and fourth boot devices. Set these options to "null" or blank. When dual booting, you will only want your computer looking to the hard drive for operating systems.
Press "Esc" and press "Y" to save changes. Your computer will reboot and be prepared to dual boot.