To cut down the mass amount of pins, this thread will serve as a hub for each of those threads.
[JTAG/RGH/R-JTAG] Xbox 360 Ultimate Exploit Guide By Oblivioncth
Beginners Guide To Using a JTAG/RGH by L14M333
JTAG/freeBOOT/XBReboot FAQ by EclipseModz
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[JTAG/RGH/R-JTAG] Xbox 360 Ultimate Exploit Guide By Oblivioncth
Beginners Guide To Using a JTAG/RGH by L14M333
JTAG/freeBOOT/XBReboot FAQ by EclipseModz
How to check if your Console is JTAG-able by EclipseModz