Partitions can be used on computers to host different operating systems on the same hard drive. For example, you can run Windows 7 on one partition and Windows Vista on another. This is useful if you want to maintain an operating system prior to software programs that would not work on the new system. The device is programmed to boot from one of the partitions by default. If you want to boot from a different partition, you will have to change the boot order. This can be done by modifying a small program called BIOS from the same computer.
Restart your computer and follow the instructions that appear on the screen to activate BIOS. These instructions usually appear for a short period of time when your computer just starts, before it starts to launch your operating system. Usually, it will say something like “Press F2 to enter BIOS”. If you can not see the instructions, check your computer’s user manual.
Use the arrow keys on the keyboard to scroll to the “Start order” or the option “Boot devices” in the menu.
Go to the “Hard Disk” option and use the “+” and “-” keys on your keyboard to change the boot order to a different partition.
Go to the “Save and exit” option from the menu and press the “Enter” button. The device will restart with the new boot command.