- The drive is manufactured by Samsung (Seagate Drives have been used in some systems. Unknown if contents are the same) and is required to play backward compatible Xbox games.
- Model: SAMSUNG HM020GI
- Revision: YU100-06
- Serial Number: S0A8J20YA44356 (of course this is different for every HD)
- Capacity: 18.63 GB
- Model: ST920217AS
- Revision: 3.01/LD25.1
- Capacity: 20 GB
- Model: HTS541020G9SA00 (Travelstar)
- Revision: C60D
- Capacity: 20 GB
- Vendor Support URL: 
- The harddisk is not locked in any way. A completely zero drive will only be read by the Xbox 360 if the relevent headers are in place on the disk.
- A FATX partition exists on the drive
- For a drive to be considered valid it must have the 'Plain text HDD info' and MS logo PNG. If these elements do not exist then no HDD is detected. So there is no way for third parties to manufacture HDDs without a license or without infringing Microsoft's copyright. (The Gameboy used the same idea for cartridges). US courts have held (in at least four separate cases) that Copyright cannot be used to prevent interoperation.
- The 360's serial number is required when formatting a HDD.
- The drive's capacity is reported as 13GB by the 360 immediately after formatting (20Gb HDD only).
- There is no information at this time that leads us to believe the HDD is encrypted, there are plenty of clear text entries that can be read.
- The FATX partitions on the drive seem to be a Big Endian version of the 1st Generation Xbox's FATX filesystem. Work is underway to modify the Linux kernel driver to verify this. There is some initial support for this file system in [CVS].
Pin # Signal Name On XBOX 360 Signal Description
1 V33 Not connected 3.3V Power
2 V33 Not connected 3.3V Power
3 V33 Not connected 3.3V Power, Pre-charge, 2nd mate
4 Ground Connected 1st Mate, Pre-charge, 2nd mate
5 Ground Connected 2nd Mate
6 Ground Connected 3rd Mate
7 V5 Connected 5V Power
8 V5 Connected 5V Power
9 V5 Connected 5V Power
10 Ground Connected 2nd Mate
11 Reserved Not connected -
12 Ground Connected 1st Mate
13 12V Not connected 1st Mate, Pre-charge, 2nd mate
14 12V Not connected 2nd Mate
15 12V Not connected 3rd Mate
This (probably) explains why normal 3.5" sata drives won't even spin up (missing 12V). So if you want to use a 3.5" drive you need to connect your own 12V.
This table plus more info can be found in the electrical specification here. (Table 17, Page 117)
- Tool to help do binary diffs of HDD images, courtesy of Daeken