If I remember right the original xbox cpu (intel) was a derivative of the 733 MHz Pentium 3, which came in a 'socket 370' package for assembly on regular x86 motherboards. It's several generations beyond the socket 7. The xbox cpu to me looks similar to the soldered onboard pentium 3 mobile interface used in laptop manufacturing at the same time, no socket, just BGA soldered onto the board.

google "pentium 3 coppermine" for some more info on the series of CPUs...