Also, the current-gen consoles from Microsoft and Sony are pretty much PC hardware-- somewhat customized APU (both the PS4 and Xbox One are based around combined CPU + GPU designs from AMD), but still derived from designs that are available as commodity PC hardware.
Nintendo's the only one that's really gone a different direction; the Switch is ARM-based and built around the Nvidia Tegra X1 (same chipset as the Nvidia Shield). Software-wise, they're (reportedly) running a derivative of the OS from the Nintendo 3DS.
