Meanwhile, the OS on an Xbox One eats 3Gb of RAM, even when games are running: http://arstechnica.com/gaming/2013/07/report-os-overhead-tak...
PS4 has a similar memory overhead for the OS.
Modern consoles are nothing like the old-school ones where once a game was running it had nigh on total control of the underlying hardware.
But this shows once again the conflictual nature of Microsoft's two strategies with the Xbox One. It's like the gaming part is more of an afterthought, and what they really want is for Xbox to become everyone's streaming box - a $400 streaming box.
This notion of "one OS everywhere" is what we'll get us a Windows 8 smartwatch with 2GB of RAM and a Celeron processor - because who wouldn't want that?!
For now. But they also have a perfectly capable $179 streaming box that blows e.g. the Apple TV out of the water performance-wise and has a large number of popular game titles.
The XBox One is apparently popular enough to sell a couple of million devices (roughly in the same ballpark as most other streaming boxes) and packs enough punch to gently go from $400 to the 360's price point.
What I wonder about is what's in it for Microsoft. First of all, the music + movie + some apps market is much larger than the hard core gamer's market. And they make it awfully hard for people to buy into their ecosystem. A $50 streaming box would make that Windows Phone (which cannot stream to Apple TV or Chromecast) much more interesting for a lot of people than having to buy a game console for streaming.
I've always thought of video games for Microsoft as a vanity project in the same way family sedan car companies build supercars. It provides a high-performance focal point for development that trickles down useful technologies everywhere else in the manufacturing process.
DirectX, for example, probably wouldn't have ever happened if Microsoft just cared about making office productivity software.
Isn't that 30% made to take care of the social features, like "sharing a clip of the last frag I just achieved" in a FPS or something like that ? If you want to have these advanced features, you need a number of tasks to run in the background and I would not be surprised by the 30% CPU time.
If you believe the rumours Dave Cutler worked on the hypervisor of the Xbox.
Since the CPU is low performance, the OS could easily eat 50% of its total performance, leaving scant little for games.