Interesting find on a website: a Power Mac G5 labeled… Microsoft. The explanation is simple: in 2004, during the development of the Xbox 360, the initial development platforms were Power Mac G5s. As the company didn’t have machines equipped with the processor of the Xbox 360, they used the most accessible PowerPC platform available…
These were entirely typical Power Mac G5s, which incidentally run Mac OS X without any issues. Unfortunately, to my knowledge, the software for this development platform was never made available, and the few kits still in existence (like this one) had their hard drives wiped.
Mac OS X
Power Mac G3