WALKTHROUGH: Setting up a RAID array in Windows
Step 1: Disk operations are carried out in the Disk Management console. Open Control Panel | System and Security, then click “Create and format hard disk partitions” – or type “disk management” into the Start menu search box. You’ll see a window like the one pictured, with assigned volumes at the top and physical disks at the bottom.
Step 2: Right-click on one of the disks you want to use in the new array, and select which type of volume to create (if you’re not using a server edition of the OS, RAID5 will be greyed out). For this example, we’ll combine two unformatted 120GB disks into a RAID0 array for maximum performance, so we select “New Striped Volume…”.

Step 3: A wizard asks which disks to include. Regular NTFS partitions aren’t available, but you can select unused space on a disk that contains another partition, such as the 93MB available on our Disk 0. The capacity of the array is constrained by the smallest disk, however, so we’ll add only the unused Disk 3 to the preselected Disk 2.
Step 4: The wizard then asks you to assign a drive letter to your array, and invites you to format your new disk. You’ll see a warning that the volumes must be converted to “dynamic” disks. This is a special disk format Windows uses for arrays: it can’t be booted from (unless it’s your system drive), and isn’t recognised by other OSes.
Step 5: Another use for RAID is to bring your system drive into a mirrored array, for safety. Attach a second disk of at least the same size. Then, convert your existing drive to a dynamic disk. This only takes a few seconds: you’ll find the option by right-clicking on the information area at the left of the drive map.
Step 6: When you right-click on a dynamic disk (shown in greenish brown), you’ll see the option “Add Mirror…”. You’ll be shown a list of suitable disks: select the volume you want to use and Windows will start synchronising the two drives. This can take many hours, but you can keep using your computer while it happens.