Xbox One: Hardware and software specs detailed and analyzed

Yesterday, Microsoft unveiled the Xbox One. Putting aside the insanity of the console’s name (Xbox 1 -> Xbox 360 -> Xbox One), we now have a fairly good idea of the software and hardware inside the Xbox One. In true console-maker style, Microsoft hasn’t told us everything, and is certainly being very coy about some parts of the new console, but we know enough that we can infer a lot of the missing details.

The Xbox One’s hardware specs

While Microsoft said very little during the unveiling itself, the information we do have seems to confirm that the Xbox One is powered by an 8-core x86 AMD CPU, and a GPU that’s very similar to the Radeon 7790. There’s 8GB of DDR3 RAM (shared between the CPU and GPU), 32MB of very fast SRAM on the graphics die, and a total of 200GB of memory bandwidth (more on that later). There’s also some new silicon in Kinect 2.0, which will come with the Xbox One as standard, which we’ve covered in a separate story. Rounding out the hardware, there’s a Blu-ray drive, 500GB hard drive, 802.11n WiFi (with WiFi Direct), HDMI in and out, Gigabit Ethernet (yay!), and USB 3.0. There’ll be three 802.11n radios, so that the console can connect to your gamepads (WiFi Direct), mobile devices, and home network without added latency.

Xbox One hardware diagram. Note the ports on the back.

So far, so good — but, when you take a closer look, it’s clear that there’s still a lot of unanswered questions. Before the unveil yesterday, it was widely believed that the Xbox One’s SoC would feature eight AMD Jaguar cores — just like the PS4. The problem is,Jaguar (and its accompanying GCN GPUs) are 28nm parts — and yet, according to some journalists who got an exclusive peek at the Xbox One, Microsoft says the SoC is based on a 40nm process. It’s entirely possible that AMD somehow backported its 28nm parts to 40nm, but owing to the significant differences between the processes this would’ve been a very costly and time consuming task. It’s worth noting that we don’t have confirmation that the PS4 uses a 28nm chip, either.

When it comes to the memory bandwidth, the Xbox One has 68GB/sec of main memory (8GB DDR3) bandwidth, 102GB/sec of bandwidth to the embedded SRAM, with the last 30GB/sec probably between the CPU and GPU, or perhaps between the CPU and peripherals (gamepads, Kinect, cable TV). The PS4, on the other hand, will just have 176GB/sec of main memory (8GB GDDR5) bandwidth. The real-world difference will probably be negligible — though I would say that the PS4 probably has the edge, as developers don’t need to pay special heed to the Xbox One’s fast-but-small SRAM.

For a more detailed breakdown of the Xbox One’s hardware, we’ll probably have to wait until the console has been released and reverse engineered by enterprising hackers and crackers. More information might be released at E3, too.

The Xbox One’s software: Three operating systems in one

Perhaps for the first time in console history, the Xbox One unveil, and the Q&A panels that followed, focused more on the software than the hardware. According to Microsoft, the Xbox One runs three different operating systems. There’s a core operating system that’s based on Microsoft’s Hyper-V hypervisor technology, which boots up when you turn the console on. This hypervisor then boots up two further operating systems: Xbox OS, which runs the games, and an OS that’s based on Windows 8, which runs the apps (Skype, TV, etc.)

The Xbox OS and Windows-based OS run side-by-side, on hardware that’s virtualized by the hypervisor. Both OSes are permanently switched on and constantly rendering their video output, to enable instant switching/snapping between games and apps/TV. The Xbox OS is rebooted whenever you load a game, but the Windows-based OS is persistent until you turn the console off. It isn’t clear how the hardware resources are split between the two virtualized OSes, but hopefully the Xbox OS (games) gets most of the RAM and GPU time.

This is a very interesting and potentially very powerful setup. I actually speculated about the Xbox One running Windows 8 way back in July 2011. At the time, I theorized that Microsoft would develop a single OS (Windows 8) and interface (Metro) that unifies every form factor, from desktop, to tablet, to smartphone, to console. While I was only half right, it’s clear from the various demos, photos, and videos that the Xbox One will look and feel like a Windows 8 device. The grid-like Metro design language is there, snapping is there, the fonts are the same. While we’ll probably have to wait until the Build developer conference to find out more, it is also very likely that apps developed for Windows 8 and Windows Phone 8 will run on the Xbox One with minimal modification.

With the switch from a PowerPC CPU in the Xbox 360 to x86 in the Xbox One, it might also simplify the development and porting of games between Windows 8, Windows Phone 8, and Xbox One. We have almost no details on the Xbox One’s gaming OS, but it’s possible that it’s also been rejigged to share more of the Windows 8 kernel.

In short, the unification between all form factors is virtually complete. In theory, this is very exciting for Microsoft, consumers, and developers. In practice, Microsoft now needs to get off its ass and shift a ton of devices so that consumers and developers can actually take advantage of this utopian unified interface and ecosystem.