On-Package PCH, The First Single Chip Haswell

In 2010, with Clarkdale and Arrandale, Intel went from a 3-chip platform solution (CPU, IOH/MCH, ICH) down to a 2-chip platform (CPU + PCH). With Haswell, we see the first instantiation of a single-chip Core platform.

With the 8-series chipset, Intel moved from a 65nm process on the 7-series chipset to 32nm, skipping 45nm entirely. An older, less mobile-focused Intel would try to keep its chipsets on the oldest, economically sensible node possible, but these days things are different. The move to 32nm cuts TDP down considerably. Intel hasn’t publicly documented the power consumption any of its ultra mobile chipsets, but if we look at QM77 to QM87 we see a 34% decrease in TDP.

In Haswell desktop and standard voltage mobile parts, the 8-series chipset remains a an off-chip solution in a discrete package. With Haswell ULT and ULX (U and Y series SKUs), the 8-series PCH (Platform Controller Hub) moves on-package. Since it’s on-package, the TDP of the PCH is included in the overall TDP of the processor.

Bringing the PCH on-package not only saves space on the motherboard, but it also reduces the power needed to communicate with the chip. Signals no longer have to travel off die, through the package, via traces on the motherboard to the PCH. Instead you get much lower power on-package communication.

Intel also changed the interface between the CPU and PCH to a new on-package interface instead of DMI. Presumably Intel’s OPI is designed for much lower power operation.

Although PCIe support remains on the PCH (6 PCIe 2.0 lanes), there’s no external PCIe interface from the CPU itself. Any hopes for pairing a meaningfully high performance discrete GPU with Haswell ULT are dead. We didn’t see a ton of Ivy Bridge Ultrabooks with discrete GPUs, but the option simply won’t exist this time around. All of the sudden the creation of Intel’s 28W Haswell ULT with GT3 graphics makes a lot more sense. Haswell ULT lacks native VGA support. Update: NVIDIA tells me that it fully supports running a dGPU off of a x4 connection to the PCH. It's not the ideal solution, but discrete GPUs will still technically be possible with Haswell ULT.

Intel adds SDIO support. USB 3 and 6Gbps SATA are both there as well (although with fewer max ports supported compared to the desktop PCH, up to 4 and 3 respectively). There’s also a lot more sharing of bandwidth between individual PCIe lanes and USB/SATA. These limits shouldn’t be an issue given the port/drive configuration of most Ultrabooks.

Introduction Haswell ULT: Platform Power Improvements
Comments Locked


View All Comments

  • Freddo - Sunday, June 9, 2013 - link

    I wonder if this CPU is powerful enough to run the PS2 emulator PCSX2 well, it require a somewhat decent CPU.
  • bakedpatato - Sunday, June 9, 2013 - link

    So the M series socketed Mobile Haswells are not getting S0ix?
  • stevechippy - Sunday, June 9, 2013 - link

    Correct, but there are U-series 28W TDP parts that aren't in the Ultrabook bracket AFAIK.
  • Kevin G - Sunday, June 9, 2013 - link

    Typo on page 7 on the Tomb Raider 1600 x 900 test graph: "Motion Blue".

  • Ryan Smith - Monday, June 10, 2013 - link

  • name99 - Sunday, June 9, 2013 - link

    "The shift of consumer dollars to smartphones and tablets instead of notebooks and desktops won’t be reversed, but a good launch here might at least help keep things moving ok until Silvermont, BayTrail and Merrifield can show up and fill the gaps in Intel’s product stack."

    I love you Anand, and I love your tech analysis. But it might be worth your team acquiring a business analyst, or at least asking those sorts of questions of your informants.

    Silvermont does not "fill the hole in Intel's product stack" because that hole is business-based not tech-based. We saw the prices of Haswell a few days ago --- $250 and way up. Meanwhile the price of a high-end ARM SoC is, what, $20? That's one hell of a difference.

    The problem intel faces is that, for many purposes, it's perfectly adequate to pay for the $20 ARM CPU rather than the $250 Intel CPU. Silvermont and the whole Atom strategy, rather than making things better make things worse. Yes, now maybe Intel captures $20 from sale of an Atom --- but that Atom is ALSO able to replace Haswell (or at least lower-end but still more expensive Intel CPUs). The SMART Intel strategy would have been to acquire an ARM ISA license, making competitive ARM CPUs at $20 (so you still capture from that market) but at least avoid competing so directly with your more expensive line.

    Intel's problems from here on out are business problems. They have to compete with an architecture that is simple enough that Apple could put together a competitive CPU starting from scratch in two years, and they have to do so using an architecture that is so complicated it took Intel 5 years to out together a competitive CPU. Meanwhile they can't charge Haswell prices to maintain the massive parallel design teams that are required to create these ever more sophisticated x86 designs.
    (And, to make life even worse, apart from the myriad own goals Intel has inflicted, they have MS in the background insisting on its charges for Windows x86, one more drag on the sale x86 in the tablet market.)
    I don't think things are nearly as rosy for Intel as do you. Technically yes, they are well-positioned right now. But they seem to be in the position of DEC or IBM in the early 80s --- technically superb, but with an extremely problematic business model. And it's business model that determines the future, more than technology...
  • rwei - Sunday, June 9, 2013 - link

    IIRC Intel does have a full ARM license. But supporting ARM by making ARM parts competitive with Intel's x86 ones would be a blow to their future ability to extract economic rent for x86, as more software targeted at ARM became available.

    Much preferable to decisively beat ARM for 1-2 generations with x86 parts - if they can manage it.
  • peterfares - Monday, June 10, 2013 - link

    ARM is going to keep getting better and better with or without Intel. It might be smart for them to have the best ARM chips because then they'd get the money from people buying ARM chips. Not too much better than the rest that it impacts their x86 chips though. Either way, I'm glad that we can get affordable x86 computers. Until Android can truly compete with Windows on the bigger screens I'll stick with x86 Windows. Android is a LONG ways away from being able to replace Windows for me. Intel is in a tough position though.
  • meacupla - Monday, June 10, 2013 - link

    The main short comings with ARM are the lack of processing power and the massive power consumption increase with faster chips. These chips are good enough for a majority of users and the OS' that run on them support just enough games and programs to keep those users happy.

    Intel, on the other hand, have chips that are fast, but need to get their power consumption and heat output lower. There's no shortage of games and programs that only run on x86, so if you need to run a specific program that won't work on ARM, your choices become quite limited.
  • Amagus - Sunday, June 9, 2013 - link

    Is the increased battery size without increasing size/weight of the system a result of a better battery/design by Acer, or is it directly influenced by Haswell (eg lighter/smaller platform)? I noticed the thing happened with the Sony Vaio Duo Haswell design...they stuck in a bigger battery (in addition to a bigger screen) but it's weight barely went up to.

Log in

Don't have an account? Sign up now