The Xbox 360 CPU

The Xbox 360 CPU

The original Xbox used a hybrid mobile Pentium III/Celeron processor, but for the 360 Microsoft went to IBM and got the rights to a PowerPC core.  The move to the PowerPC instruction set meant that there would be no direct binary compatibility with older Xbox titles, but the sacrifice was obviously deemed necessary by Microsoft. 
The CPU itself features three of these PowerPC cores and is currently manufactured on a 90nm process, however Microsoft will most likely be transitioning to 65nm as soon as possible in order to reduce the die size and thus manufacturing costs.  Remember that a die shrink from 90nm down to 65nm will cut the size of the CPU in half, and should be possible for Microsoft sometime before the end of next year.

Disassembling the Internals of the Xbox 360

Disassembling the Internals of the Xbox 360

To continue further, you will need to first remove the DVD drive. Simply hold the drive and lift up. You will notice that the Xbox 360's DVD drive uses a Serial ATA interface which keeps things very tidy compared to the original Xbox. At this point, remove both the power supply cable and Serial ATA cable from the DVD drive and then from the motherboard.