USB hard drives are convenient because they can store and transport large amounts of data. Because the capacity of these drives has increased so rapidly in recent years, it is also feasible to use an external USB hard drive as a computer's primary drive.
In order to launch an operating system, and thus run your computer, from an external storage device, however, you have to configure your computer's BIOS to boot from a USB hard drive. Though this process is simple, it is not possible on all computers.
To determine whether your computer can boot from a USB hard drive, and to configure your BIOS to do so if it is possible, follow the steps below.
- Turn off your computer and disconnect all external drives, including the USB hard drive you would like to boot from.
- Turn on the computer and wait for the BIOS screen to appear. The BIOS screen is usually the first screen that appears when a computer is booting up. When it appears, press the Delete key to access the BIOS settings. (Note: On some computers, a key other than the Delete key is used to access the settings. If this is the case, follow the on screen instructions to access your BIOS settings.)
- Scroll down to the "Boot Device" heading using the arrows on your keyboard and press Enter. This will display a list of devices from which your computer can boot. If there is no USB option in this list, your computer cannot boot from a USB hard drive. If USB is listed, choose that option and set it as the primary boot device.
- Connect the USB hard drive to your computer.
- Save your changes and exit the BIOS settings by pressing F8. This will restart your computer. When it restarts, it will boot from the USB hard drive.
To restore your BIOS settings to boot from an internal hard drive, simply repeat the steps above. Restart the computer, enter BIOS settings, and reselect the internal hard drive as the primary boot device.