Power Gating

Until the Atom Z600 series, the only Intel CPUs to power gate were the Nehalem/Westmere derived chips. In Moorestown, everything is both power and clock gated.

The CPU itself has its usual power states; C0 implies full power, full performance, and C6 is a deep sleep state where power is shut off to the entire CPU and state is saved in a small amount of active SRAM. There’s finer grained clock and power gating in Lincroft than in Intel’s Core i7.

Moorestown is a SoC platform however, so we need some new power states. Intel calls them S0i1 and S0i3. As with CPU power states, the higher the number, the more that’s shut off.

Virtually all blocks in Lincroft and Langwell are clock and power gated. In S0i1, everything from the CPU and GPU to interconnects are power gated. From the sounds of it, S0i1 is where you’d find your smartphone if you just left it on the table for a few seconds. The display would shut off and all internal components would be power gated. Pick it back up, hit a button and you get pretty quick recovery.

S0i3 however completely powers down virtually all components and keeps a small amount of SRAM active with state data. This is the phone locked and in your pocket state.

Getting out of these power states is relatively quick. S0i3 takes around 3ms while S0i1 takes 1ms.

The impact of these idle states is huge. On a reference Moorestown platform (this includes the Moorestown chips, display, 3G radio, basically a fully functional phone), Intel measured total platform power in S0i3 at 21 - 23mW. That’s a ~50x reduction compared to Menlow, and that’s what makes Moorestown suitable for use in a smartphone.

Power Management: Clock Down or Turbo Up OS Driven Power Management
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  • Suhail_kapoor - Wednesday, May 5, 2010 - link

    Anand, Intel said 3 out of 5, you said one magic device, I think they have one sorted out ... NOKIA is a company needing revolution and this partnership is Nokia's hope for smart phone market.

    Also outside US and to some extent Europe Nokia has a very strong foot hold, combined with essentially free software such as MeeGo the road looks good, only IF and a big if, they can deliver on software front.
  • WaltFrench - Sunday, May 9, 2010 - link

    “…NOKIA is a company needing revolution and this partnership is Nokia's hope for smart phone market.”

    Only problem: Nokia needs a polished solution fast—its average sales price is imploding and the shareholders are restless. A solution that would require them to throw away all the development work to date would be suicidal.

    If it takes 12-24 months to implement a totally new architecture, with new software (seems a bit optimistic), only a smartphone maker whose roadmap is in great shape today can afford to make the switch; that'd be Apple. But they have just bulked up with PA Semi and Intrinsity; it'd be hard to imagine much Intel Inside.

    Not to mention that Intel's i-series CPUs seem to have been designed to derail Apple's plans of running with a graphics-centric, well-supported CPU. The extra silicon & design time seems to have kept the i3 out of Apple's 13" notebook, while the 15" and 17" have just-a-bit-rocky auto-switch technology to fire up the NVidia GPUs. It doesn't seem that Intel has exactly been courting Apple's product intentions of late.
  • Lord Banshee - Wednesday, May 5, 2010 - link

    Intel First SoC based on Atom is not Moorestown, but CE4100(codename Sodaville) is: http://download.intel.com/design/celect/prodbrf/32...

    http://intelconsumerelectronics.com/

    Where is the love for Intel's CE product. Anand you should look into reviewing some products based off these products too.
  • ganeshts - Wednesday, May 5, 2010 - link

    Sure, is there a shipping product based on the CE3xxxx or CE4xxxx series?

    I remember there seemed to be something like the Yuixxx from Conceptronix or some similarly named Dutch company.. Did they ever ship?
  • Lord Banshee - Wednesday, May 5, 2010 - link

    I am not sure what products have CE products in it... CE devices typically don't advertise this kind of info.

    Lots of rumors when searching for ce4100 on engadget

    http://www.engadget.com/search/?q=ce4100&invoc...
  • ganeshts - Wednesday, May 5, 2010 - link

    Most of those CE4100 results are Intel announcements announcing platform updates or availabilities.

    The TiVo Premier result, I am not sure why it is even there.... TiVo Premier teardown revealed it is fully Boradcom based, IIRC.

    I am very interested to know whether there are any CE4100 products out in the hands of the customers right now... Any Intel employees / PR guys care to offer this information?
  • zdzichu - Wednesday, May 5, 2010 - link

    Seeing that GPU part is descendant of Paulsbo... I foresee similar fiasco with opensource drivers as with GMA500. Too bad, it really damages Intel reputation.
  • beginner99 - Wednesday, May 5, 2010 - link

    funny gma 600. Even if intel like improves gm drivers 100x fold, they will still suck...So you can pretty much say it depends on that.

    And there go my dreams for useful drivers for my menlow device...it's a PITA. slowing hardware by deliberatley? making horrible drivers.
  • JumpingJack - Wednesday, May 5, 2010 - link

    Intel's graphics performance as they begin integrating into the CPU improved significantly, to the point of competitive. http://www.anandtech.com/show/2952/2

    Your view point is strictly from a desktop running pixels number as high as 1900x1200 (too much for even the best IGP from nVidia or ATi/AMD), on a smartpone the graphic intensity is not nearly enough... it does not need to win on the highest FPS, it just needs to get 30 FPS or better for a fluid experience.

    The graphics component should be fine, no real reason to suspect otherwise.
  • rahvin - Wednesday, May 5, 2010 - link

    Given the abysmal Linux support of the GMA500 I foresee a complete piece of crap again that will result in this being used in NO android phones. For me Android is the future of the cellphone and frankly what happened with Paulsbro foreshadows the complete crap that this platform will be on Android and other Linux based platforms (like WebOS). The concerns of the OP are completely justified and I had exactly the same reaction when I read the GPU is based on PowerVR like the piece of crap GMA500.

    Intel cannot succeed in the Phone space if Linux is treated with the same disdain they presented with GMA500.

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