It's basically what Xemu (and XQemu before it) are doing. They have a slightly more easy job though, as the entire OG Xbox architecture is basically a slightly

It's basically what Xemu (and XQemu before it) are doing. They have a slightly more easy job though, as the entire OG Xbox architecture is basically a slightly hacked x86. Still, the console-specific stuff like the GPU does require very accurate emulation.