What's new/fixed (since v3.3)
* MS28 core firmware. Also better and faster media detection.
* FirmGuard added. On by default. Firmware cannot be Read/Written by 360 console. Can ONLY be turned off (Read/Write enabled) via Enable0800 mode.
* 4.0A firmware. 4.0A is default Fast Read Speed mode. Quite/Slow Read mode for backups activated via any Xbox 360/Xbox 1 Original game disk.
* 4.0B firmware. 4.0B is default Quiet/Slow Read Speed mode. Fast Read mode for backups activated via any Xbox 360/Xbox 1 Original game disk.

Some details about new features:
* For Xtreme 4.0A default backup Read Speed is same as original game disks 12x. When Original Game disk is booted, all subsequent backup loading will be at Quiet/Slow Read mode, Original Game disks are unaffected. Turn console off/on to reset back to Default backup read speed (12x). Quiet/Slow Read Speed is for quiet operation and/or cheap DVD+R DL media.
* For Xtreme 4.0B default backup Read Speed is Quiet/Slow 2-4x. When Original Game disk is booted, all subsequent backup loading will be at Fast Read mode 12x, Original Game disks are unaffected. Turn console off/on to reset back to Default backup read speed for backups (2-4x).
* FirmGuard disables reading/writing of drive firmware. This is always on. Can only be turned off via Enable0800 mode. Do not have SATA cable plugged into Xbox 360 console when in Enable0800 mode.

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