Microsoft XCPU, codenamed Xenon, is a CPU used in the Xbox 360 game console, to be used with ATI's Xenos graphics chip.

The Xbox 360 S introduced the XCGPU (codename Vejle), which integrated the Xenon CPU and the Xenos GPU onto the same die, and the eDRAM into the same package.

The XCGPU follows the trend started with the integrated EE+GS in PlayStation 2 Slimline, combining CPU, GPU, memory controllers and IO in a single cost-reduced chip.

It also contains a "front side bus replacement block" that connects the CPU and GPU internally in exactly the same manner as the front side bus would have done when the CPU and GPU were separate chips, so that the XCGPU doesn't change the hardware characteristics of the Xbox 360.

Compared to the original chipset in the Xbox 360 the combined power requirements are reduced by 60% and the physical chip area by 50%.