1: Set up your IPREP folder.
2: Load your firmware either 2x, 5x, 8x, 12x.
3: Choose your VIA SATA card.
4: Then choose your drive destination to create the IPREP folder in. (In my case it was C: as I'm using NTFSDOS but if your using a floppy it will be A:\ or if it's USB either F:\ or G:\.
5: Copy FIRMTOOL from the Firmware folder that you downloaded from Xbins and paste it into C:\IPREP or where ever your IPREP folder is.
6: Then copy your orig.bin file into the same C:\IPREP.
7: Open Command Prompt by choosing run from the start menu and typing CMD and pushing enter.
8: Get to your C:\IPREP folder and type the following: firmtool orig.bin ixtreme.bin and press enter.
9: The following screen should appear and your hacked firmware will have the same key as your original.
10: You can check if the keys are the same by using Firmware Toolbox 4.5 but it's not really necessary.
11: Now time for the FLASH
12: Turn off your PC and hook up the X360 ready to be flashed.
13: Connect the XBOX 360 metal case and PC metal case together with copper wire.
14: Unplug the SATA cable from the XBOX 360.
15: Turn on PC and XBOX 360 at the same time.
16: Boot into DOS.
17: Once at the DOS Prompt Screen plug the SATA cable into the XBOX 360.
18: Get into your IPREP folder.
19: Type "MTKFlash w /m ixtreme.bin".
20: The following screen will appear.
21: At this scree turn off the XBOX 360.
10. Choose your PORT (e.g. 2. XTREME PRI MASTER) Press 2.
11. An ERROR MESSAGE appears.
12. Count to 10.
13. Turn the XBOX 360 back on.
14. MTKFlash will flash the XBOX 360 and the new firmware will be on the drive.
15. Put the XBOX 360 back together and ENJOY the multispeed gaming experience. I'm using 8x at the moment. It is working great. The sound is quite and the lag is minimum.