The original tutorial : http://gueux-forum.net/index.php?showtopic=167103
Sorry for english.
(My DVDkey is now 12121212121212121212121212121212)

You need in harware :
- xbox 360 4532 or 4548
- Infectus modchip
- PC with XP

You need in software :
- the Infectus Programmer v.0.0.3.4d
- a hexadecimal editor (hex workshop)
- Flashtool 0.81
- the NAND.bin file
- the 1BL.bin file
- the FUSES.bin file


The 3 last files can get with this tutorial : http://forums.xbox-scene.com/index.php?showtopic=621052

To change the dvdkey, we patch the NAND.bin with the KV.bin file (keyvault).
To have the KV.bin file, you need the CPUkey, Flashtool and the NAND.bin.
To patch the NAND.bin by the KV.bin files, you need the 1BLkey.

Sight glogale:
Diagram 1 : KV.bin :



Diagram 2 : the NAND patch :




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A/How to have the CPUkey :
The CPUkey is in the FUSES.txt file.
Open the FUSES.txt file with blocnote, delete all lines exept the lines 3 and 5 (or 4 ou 6).
CPUkey = line 3 + line 5



Save in CPUkey.txt .


B/How to have the 1BLkey :
The 1BLkey is in the 1BL.bin file.
Open the 1BL.bin file with your hexadecimal editor and Goto offset 5878



The key begin is in 5878 and the end in 5887.



Copy the 32 digits in 1BLkey.txt .

C/Keyvault creation, KV.bin : (diagram 1)
Now, you are 2 keys and the NAND.bin file.
- Open Flashtool .
- Select Keys
- Open near the 1BLkey.txt and CPUkey.txt .
- Copy/Paste the keys and OK :



- Press Dump Files and select the NAND.bin file.



- Press Extract , select Key Vault and OK . Save.

The KV.bin is created (16 368 octets).

D/KV.bin modification :
The DVDkey is in the KV.BIN .
- Open KV.BIN file with your hexadecimal editor and Goto offset F0 :



The key begin is in F0 and the end in FF

- Change the DVDkey .



- Save the change.

Now the KV.bin file is ready for the nand.bin patch.

E/NAND.bin patch : (diagram 2)
- Open Flashtool :
- Choose Patch
- Cross Patch Keyvault and press Browse...



- Choose the KV.bin file and OK . Save the new NAND in NAND2.bin .

It's OK. The nand is patched and his name is NAND2.bin .

F/ Flash the motherboard :

- Launch the Infectus Programmer .
- Connect the USB cable to the Infectus
- In Flash Command select Erase.
- In Flash Command select Blank Check .
- In Flash Command select Write . Choose the NAND2.bin file and Open .
- Disconnect the Infectus.
- Close the programmer.

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A special THANKS to zouzzz for this tutorial!!

thanks also to SeventhSon, robinsod, uberfry, Jx7, Xfab29, bonx and the gx-mod forum.