Xbox One Review: Unifying Your Living Room Experience

The Xbox One CPU: Complements Of AMD's Jaguar µArch

A Familiar CPU Architecture

The Xbox One's CPU component brings Microsoft’s architecture of choice back to x86, just like the first-generation Xbox. This time, the company kicked IBM to the curb and opted not to jump into another Intel/Nvidia love triangle. Instead, it put a ring on AMD's finger, tapping the same source for general-purpose and graphics computing IP. At the same time, Sony was courting AMD's semi-custom division as well. Both competitors ended up sharing a bed, but due to NDAs was never caught laying down.

When AMD acquired ATI back in 2006, the company promised integrated graphics paired with x86 resources. It took a while, but we saw the first deeply collaborative effort in AMD's Brazos platform for very low-power devices. While it proved to offer notable advantages over Intel's slow Atom, even the Zacate-based E-350 wasn't a performance powerhouse. Not long after, we were introduced to the Llano-based design, which existed primarily on the desktop between 65 and 100 W. But it was still a far cry from achieving the numbers we wanted to see in any one discipline.

Although even today's Richland-based APUs don't get us where one capable CPU and even mainstream discrete graphics can go, AMD did gain the experience needed to create a modular architecture with right-sized CPU and GPU resources to build more customized processors. And that's exactly what it did for Microsoft's Xbox One.

At the heart of AMD's Temash and Kabini APUs (covered in AMD's Kabini: Jaguar And GCN Come Together In A 15 W APU) is the energy-efficient Jaguar CPU architecture. It's an enhancement of the previous-gen Bobcat design, which powered the aforementioned E-350 and went up against Intel's Atom.

Jaguar maintains many of Bobcat's features, such as some of its cache structures, the ability to decode two instructions, and a similar branch predictor, but adds a number of enhancements covered in our linked launch coverage and summarized in the slides on this page. There's an extra decode stage in the front-end, though this plays a role in achieving higher operating clock rates as well.

In AMD's APU portfolio, Jaguar has access to a shared cache unit with 2 MB of L2 that's 16-way associative in quad-core configurations. The L2 is broken up into 512 KB banks, but no longer associated with each core, as it was before. Both the Xbox One and Sony's PS4 employ eight Jaguar-based cores. But because Jaguar supports four-core arrays, these next-gen consoles actually implement two modules, doubling total L2 to 4 MB.

Compared to what we're used to seeing in the desktop PC space, Jaguar is comparatively simple. Each core occupies 3.1 square millimeters of die space. Even with eight of these on a die, that's only 24.8 square millimeters. It's this efficient design that makes Jaguar viable in such a parallelized SoC, particularly matched up to a much more complex graphics component. Programmed to properly, Microsoft should be capable of great multi-tasking capabilities as the Xbox One runs social media, Skype, and Kinect-oriented tasks with minimal impact on gaming.

In fact, we recently spent some time on the phone with Johan Andersson of DICE, who mentioned that his team is seeing 85-95% CPU utilization on next-gen consoles by virtue of optimizations for scaling in its Frostbite 3 game engine. It looks like the developer community is really ramping up efforts to more thoroughly program to many cores, which could yield great returns on the PC, too.

Microsoft's first developer kits featured 1.6 GHz x86 cores. For production, frequencies were boosted to 1.75 GHz. Although combining a less potent architecture with fairly conservative clock rates might appear to leave the Xbox One underpowered, there's a lot of emphasis on parallelism. And not only in the CPU structure, but also offloading compute tasks to the graphics engine. This is where AMD's HSA efforts will hopefully bear fruit.

Create a new thread in the US Reviews comments forum about this subject
This thread is closed for comments
74 comments
Comment from the forums
    Your comment
  • lostgamer_03
    Great review, really made reflect over what a gaming machine should be able to do nowadays. A gaming machine isn't just a gaming machine anymore and the Xbox One, even though it might not be as powerful as PS4, is a really attractive product in my perspective.
    6
  • Ceee9
    any Am%$^$N want to trash this?
    0
  • Nahkman
    Reinventing the TV experience only applies to the Americas as the rest of the world does not really care much about ESPN, and also a lot of the functionality is NA only, there was also a rumor that kinect voice commands do not work in a lot of european countries.
    1
  • Maziar
    Great review
    At the time being,IMO PS4 is a better gaming machine;whereas,X1 is a better entertainment system.
    PS4 has a more powerful GPU so it should perform better in games and is $100 cheaper too;whereas,X1 tries to do more than just gaming and costs more.
    For me,PS4 is a better machine because I only tend to play games on a console but X1 is also a great machine
    4
  • de5_Roy
    10 pages and.. nothing about xbone(R)'s gaming capability or gaming experience. the review was done well, but seems restricted to media capabilities. the device seems versatile.
    some of the ps4 reviews i read had info on gaming as well as media/entertainment. i mean info like how the games look and feel to a player, resolution and user perception, joystick (and other input devices) performance in gaming etc.
    2
  • daglesj
    As a 42 year old that back in 2006 played a lot of games on my console but now mainly uses it for media and streaming with a bit of gaming on the side (I'm sure I'm not the only one) the Xbox One is a more compelling unit than the PS4.

    I'm pretty sure MS went over the usage stats of the 360 and found that more and more people were using the media/TV/movie aspects. After all thats where the money is.

    MS could sell half as many Xbox Ones as Sony but it will still be making far more per console in subscriptions and services. The money going forward isn't in games.

    However, I don't think this generation will be as long lived as the 360/PS4. I see One.5 or PS4.5 models or total replacement within 5 years.
    1
  • zzzaac
    Unfortunately all these nifty things are half working or not working at all for countries other than US of A

    I might be getting both, but to be honest I might not get any, as I've become more of a PC gamer
    3
  • daglesj
    delete
    0
  • daglesj
    delete
    0
  • cats_Paw
    I think im getting old, becouse when i read this i think that the Xbox one is basicly a low end PC with limited usability...
    1
  • daglesj
    Holy moly what other web forum keeps your comment hidden below and adds it every time you refresh the page???

    One day Tom's will move into the 21st century. Apologies folks.
    0
  • Yuka
    Ugh... I think Microsoft tried (and wants to) put in the same bag as much people as possible with the XBox One. Just like the Wii did at first with the "casual" games and first party "hardcore" games (yeah, whatever).

    It is not a bad thing when done right, yes, but then you'll have a "jack of all trades" instead of a "gaming machine". I'm not an advocate of putting too many specific functions into one device until the technology is up to par with the individual ones. Smartphone cameras is a fine example for that: today we find "good" picture quality compared to a Point and Shoot and it will get even better down the road thanks to tech advancements. In the case of consoles, I expect SteamBox to trash everything else in the living room gaming wise first and other-stuff second, including the recent-out consoles. There's a world of horsepower of difference between the custom APUs and using an Intel + nVidia/AMD video card with an optimized OS (SteamOS, remember?).

    I'll need a first hand experience with the XB1 and the PS4, but as "consoles", they must not disappoint. Kinnect is a feature you should/can put in a PC/HTPC with little effort if you want one (we're in a tech site, so this phrase is valid). Same for the EyeToy. Hell, even speech recognition used in the XB1, I'm sure is a derivative from the one in Windows that anyone can actually tune and use.

    Cheers!
    1
  • Jgriff
    look at that new and improved steam controller, thats all i see when i look at the x1
    -1
  • SteelCity1981
    So basicly the xbox one has a bunch of stuff that I already have on my tv and cable box, which makes its features pretty much useless to me. Already have a smart TV don't need another smart deivce. Already have a DVR, don't need that either. Also I find some of the features they put on there rather dumb. if I'm playing a game why would I want to Skype with someone or watch tv at the same time, which would distract me from playing the game in the first place! I don't need a Kinect so why would have to shell out an extra 100 dollars for something I don't want not to mention I don't have the room for it. if microsoft was actually smart they would bundle the xbox one without a Kinect and cut the price by 100 dollars to compete with sony I just think that Microsoft really missed out here.
    5
  • rsktek
    The reasons why the Xbox One is not the right choice for me ( I appreciate what they tried to do ) is that I DON'T HAVE CABLE, rural USA doesnt have that available. So all the TV functionality is pointless :/ Also, having a tablet, like the Nexus 7 along with you as you're playing games or watching Local TV, I don't see Kinect and its voice commands being any faster than searching stuff on the tablet. Just my 2 cents (Disclaimer: Not getting any Next Gen machines, only appreciate them pushing developers to use more CPU resources AKA better PC ports)
    2
  • tuanies
    Anonymous said:
    Great review
    At the time being,IMO PS4 is a better gaming machine;whereas,X1 is a better entertainment system.
    PS4 has a more powerful GPU so it should perform better in games and is $100 cheaper too;whereas,X1 tries to do more than just gaming and costs more.
    For me,PS4 is a better machine because I only tend to play games on a console but X1 is also a great machine


    We'll have more stories on both consoles.

    Anonymous said:
    10 pages and.. nothing about xbone(R)'s gaming capability or gaming experience. the review was done well, but seems restricted to media capabilities. the device seems versatile.
    some of the ps4 reviews i read had info on gaming as well as media/entertainment. i mean info like how the games look and feel to a player, resolution and user perception, joystick (and other input devices) performance in gaming etc.


    The problem is a lot of the functionality is limited until the day one update, which the press samples did not have yet. We will have follow ups in the coming weeks. I'll be out camping for mine Thursday night :)
    0
  • rsktek
    *Edit I hope this doesn't double post -_-
    0
  • cknobman
    Wow the review really put in perspective just how big and ugly the Xbox One is (physically). It will make my XBox 360S look like a midget.

    The Xbox One may be an astounding piece of technology but it looks fat and ugly.
    0
  • expl0itfinder
    I don't think this is a very relevant console compared to the PS4 (for a gamer). The value is just plain bad for a gaming machine. This is mainly because of the price point. There is no significant advantage over the PS4 to justify a $100 price bump IMHO.
    5
  • monkeycmonkeydu
    This thing is simply a low end DVR that happens to be able to play a few games, while the PS4 is actually optimized for games and can do a few simple media functions. Anybody who buys this thinking it will compete with the PS4 in gaming quality is an idiot.
    -2