How to Dual Boot With Two Hard Drives

By Jeff Grundy

Dual booting or multi-booting allows you to test multiple operating systems on one machine.
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Windows has ruled the desktop operating system market ever since Microsoft teamed with IBM to produce the software for the first line of PCs in the 1980s. Even with other OSs available for PCs, Windows continues to dominate the market by a wide margin. Nevertheless, alternate operating systems may offer applications or features you want to test or try. Alternatively, you may simply want to install two versions of Windows. If your computer has two hard drives, you can install a second operating system on the second drive and set up the machine so you can choose which OS to boot at startup.

Step 1

Shut down the computer and restart it. As soon as the machine starts to boot, insert the installation disc for the secondary operating system into the optical drive of the computer. Ensure that you insert the disc before the Windows logo appears on the screen or you will have to reboot the computer with the disc inserted. Wait for the computer to boot from the installation disc and display the initial setup menu for the second operating system.

Step 2

Click the "Install" or "Setup" button in the setup screen for the second operating system. When prompted to choose a drive for the installation, select the primary partition for the secondary hard drive. If your primary Windows hard drive has only one partition -- the "C:" drive -- the secondary drive's partition probably uses the "D:" drive letter. If the hard drive with Windows installed has two partitions -- the "C" and "D" drives -- the drive letter for the main partition on the secondary hard drive probably uses the "E:" drive letter unless you changed it manually using the Windows Disk Management utility.

Step 3

Follow the remaining prompts to create additional partitions on the secondary drive if needed and format the drive with the needed file system. Follow any prompts to allow the installation routine to copy needed files and personalize the operating system. Reboot the computer when prompted. After the computer restarts, a new "Windows Boot Manager" appears on the screen prompting you to select an operating system to boot.

Step 4

Press the down-arrow button to highlight and select the "Windows 7" boot option if it does not appear first on the boot menu. Press the "Enter" key to boot in to Windows 7 normally. Log in with your Windows username and password if prompted.

Step 5

Click the Start button, then type "msconfig" in the search box and press "Enter." After the System Configuration window appears, click the "Boot" tab.

Step 6

Click and select the name of the operating system that you want to boot by default when the computer starts. When you install most secondary operating systems, Windows 7 remains the default OS on bootup. However, this may not always be the case. Nevertheless, select the operating system that you want to boot automatically if you do not select an OS in the Windows Boot Manager screen.

Step 7

Enter a value in seconds in the "Timeout" field. This is the amount of time the Windows Boot Manager screen appears and waits for you to select a boot option. The default Timeout value is 30 seconds. However, you can enter a lower value if you don’t want to wait a full 30 seconds for the machine to boot to the default OS, or enter a higher value if you usually require more time at bootup to select an OS to which to boot.

Step 8

Click "Apply," then "OK" to save the boot menu changes. Restart the computer and use the Windows Boot Manager to boot into the operating system you want to use.