I read and copied and pasted some guides and came up with this hybrid guide:
How to Use:
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1. Load your floppy disk or connect your USB Flash Drive. (optional)
2. Run iPrep.
3. Detect your sata chipset, if required.
4. Open your Xtreme Firmware's .bin file. (Use 8X to read media better and 360 will also be more quiet; this would be the Benq iXtreme v1.1 Multispeed firmware)
6. Click "DO IT!". (or click "Prepare destination" in later versions)
7. Make sure the 360 power and video cables are plugged in (video doesn't have be be connected to tv). Make sure your 360 is touching your pc case to level the voltage (see below). Turn on your 360 and PC at the same time. Once your PC is booted from USB or CD (to DOS), connect the 360 sata port to the primary "0" internal SATA port of your pci sata card, usally the one closest to the front of your pc. Boot from your prepared drive or your NTFS cd (you may have to configure BIOS to boot).
8. Type "iDump xxxxxxx xxxxx" to backup your 360's original firmware and create your hacked firmware.
9. Type "iFlash xxxxxxx xxxxx" to flash the hacked firmware.
(Don't include the quotes, and replace x with your 360's Serial Number.)
*** The XBOX360 uses a floating point ground. Your PC uses a ?true earth? ground. This difference can cause excess voltage to travel through your SATA cable and potentially damage your XBOX360 DVD drive or PC Motherboard / SATA card. You can solve this problem by connecting the XBOX360?s ground to the PC?s ground. The easiest way to do this is by using a ?croc clip wire? and connecting the XBOX360 metal casing to your PC?s metal case. You can use anything conductive to connect the XBOX360 case is connected to the PC case. You don?t have to use croc clips, you could just tape some bare/stripped wire to each, or even set the XBOX360 next to the PC so that they are touching. ***
*** For some reason, when using the external ports on the PCI SATA cards, or the ?1? port if using internal it will not detect the XBOX360 DVD Drive. Use the primary ?0? SATA port.This is an internal port. If there are multiple internal ports, use the port closest to the front of your PC. ***
