Upgrade Your Xbox 360's Hard Drive on the Cheap

Use a Torx screwdriver to open the drive enclosure, exposing the interior drive cage. Next, remove the four screws holding the drive into the cage.

With the retaining screws removed, disconnect the drive from the SATA-and-power cable, and slide the drive out of the enclosure.

With your PC turned off, unplug any other SATA devices and then connect the new Scorpio drive to one of the SATA cables and to a power lead.

Afterward, boot from your DOS thumb drive (specify a boot drive in your PC's BIOS, if necessary). At the DOS command line, type "run hddhackr –f" (don't include the quotation marks) and press Enter. You'll be prompted to make a backup of the original drive firmware; do so. Continue with the process to flash the firmware on the new hard drive. After a few seconds, you'll be prompted to re­­start the computer. Once you have done so, run the "hddhackr –f" command again, and it should report that the hard drive has been formatted for the Xbox 360.

Remove the newly formatted 120GB drive from your PC and install it into the Xbox 360 drive enclosure. Put the enclosure back together, reattach it to the console, and turn the console on. Follow the prompt under 'System, Memory' to format the new drive; after formatting is complete, the drive will be ready for use.