Broadwell-Y: Introducing the Intel Core M Processor
The new 14nm node will be leveraged across multiple product segments, from data centers to tablets,via three separate Broadwell dies. For now Intel limited the information it shared with us to the mobile-oriented Broadwell-Y chip. We are told to expect an increasing amount of details on the other Broadwell products over the next quarter, with more to come during next month's Intel Developer Conference (IDF), but for now we'll have to remain content with details about the low-power mobile spin of this chip. Of course, improvements to the Broadwell core architecture will be reflected in the other dies, too. With that in mind, let's take a closer look at Broadwell-Y, marketed under the Intel Core M moniker.
The new Core M brand will cover all of the mobile space, and Intel told us that other brands like the Celeron and Pentium M will not be applied to the Broadwell-Y SoC. While the company did not disclose any actual model numbers or clock speeds, it stressed the new chip's capability to drive a hypothetical 7 to 10mm-thick fanless form factor with a 10.1" display, enabled by a 3 to 5W version of this processor. We were allowed to handle a working prototype in the form of a sexy 7mm-thin tablet, but were not allowed to run any software or examine specifications via the control panel. Until we have a working model to test, we'll have to take Intel's word that Broadwell-Y provides a "greater than 2x reduction in TDP with better performance than Haswell-Y".
We do have some specifics when it comes to the die and package sizes though. The Broadwell-Y chip is 82mm2, scaled down about 63% compared to Haswell-Y's 130mm2 die size. As for the board package, Broadwell-Y has a 50% smaller surface area and 30% thinner package compared to Haswell-Y. Part of this reduction is made possible by the relocation of the 3DL modules to a separate, tiny PCB that is attached to the bottom of the Broadwell-Y package. Of course, motherboards will need to have an appropriately-sized hole cut to accommodate it.
Because area scaling was better than expected on the 14nm node, Intel added 20% more transistors for increased features and performance. For instance, Haswell-Y's integrated graphics has a maximum of 20 AUs, while Broadwell-Y can use up to 24. That's 20% more compute resources, and Intel also claims a 50% increase in graphics sampler throughput. The company also mentions geometry, Z, and pixel fill performance improvements due to micro-architecture changes, though the company hasn't yet been specific about what these are. 4K display compatibility was also trumpeted, and two of them are theoretically supported, but practical power draw limits for a mobile device probably make this an unlikely scenario.
Intel's Core M: Focused on Low Power
Intel claims that the Broadwell-Y 14nm design and process optimizations account for the 2x lower power than Haswell-Y, which enables fanless functionality. The key SoC statistics include 25% lower power thanks to capacitance improvements, 20% less power thanks to lower minimum voltages combined with design optimizations, up to 15% improved transistor performance at low voltages, about a 10% reduction in power thanks to lower transistor leakage, and a smaller, denser processor. Of course, Intel hasn't disclosed the specific TDPs of the products that they've based these claims on, so we'll have to wait a bit longer for more information. We do know that the chips Intel is talking about have a 10 to 15W high burst speed for quick response, followed by a three to four watt sustained operating speed a few milliseconds later under load.
Broadwell-Y features the second-generation implementation of Intel's Full Integrated Voltage Regulator (FIVR), which can speed the transition between idle and load clock states. FIVR now features non-linear droop control, and a new dual FIVR LVR mode has been added. It turns out that FIVR is not particularly efficient at very low voltages, so it can now be bypassed when necessary to save power.
The SoC has an extensive list of optimizations that target active power reduction: design process optimization to reduce minimum operating voltage and dynamic capacitance (Cdyn), a re-architecture of DDR/IO/PLL/Graphics, optimizations for Cdyn in IA/Graphics/PH, and lower operating frequency ranges for IA/GT and Cache. There are other enhancements, too, such as dynamic display voltage resolution. Graphics can be controlled by Duty Cycling Control (DCC) to reduce usable power, or even turn it on and off as necessary. The latency needed to switch the GPU on and off is negligible, and it can be reduced to as low as 12.5% of its rated operating frequency.
Clock rates are, of course, tied to both power usage and thermal output. Three boost states are leveraged to deliver the highest possible clocks while maintaining system stability. The PL3 boost state allows the most amount of power that won't damage the system's battery, used for very short spikes as needed - the kind of time spans that are measured in milliseconds. PL2 is the standard burst limit, and PL1 represents the long-term system limit of sustainable power delivery. If necessary, duty cycle throttling can turn blocks of the processor on or off to minimize power usage and heat generation.
The power and thermal management framework is handled on a system level, by tracking multiple components to measure and change as necessary. This is controlled via Intel's Dynamic Power and Thermal Management software driver.
Intel's Platform Controller Hub (PCH) has also been re-engineered for Broadwell with an eye toward power efficiency. Idle power has been reduced by 25% compared to 2013, and active power has been dropped by 20% versus Haswell's PCH-LP. There are new power domains, and a new power reduction in firmware, hardware, and software updates which include fine-grain monitoring and reporting.
In addition to power enhancements, the PCH has been improved with an Audio DSP upgrade that includes more SRAM and higher MIPS. Advanced post-processing is available, with new wake-on-voice functionality. There are also fresh management and security features. Note that the PCH is manufactured using the 22nm node, so it hasn't shrunk.
Conclusion: Promising Statistics For Intel's Core M
We probably won't have access to test Intel's Broadwell CPU for a few months at least, but based on what we've seen, the company has lived up to the lofty expectations it has set. As we mentioned in our introduction: smaller processors, lower power usage, higher performance per watt, and similar overall performance compared to the previous generation at comparable clocks. All of those attributes are very desirable from a consumer standpoint.
But a lot of questions remain this early in the game. What kind of clock rates can we expect from Intel's 14nm node? How will the GPU scale compared to Haswell? What kind of Core M pricing can we expect, and will it be low enough to inject some life into low-cost Intel tablets? All of these questions will be answered over time, and we hope that at least some of them will be answered at IDF next month. Until then, we can certainly see a lot of potential in the upcoming Broadwell line.




What Gaurav Rai said:
"Meanwhile Amd innovates with 220W processsor XD"
Was humor. You know, like Ha-ha and stuff?
at 4.6Ghz my 2700K is more than a capable CPU .
Bring on the Skylake,, then we'll talk .
I would expect this to also translate into even more unpredictable and voltage/temperature-sensitive overclock outcomes.
thus beat amd. but, to me, amd chips like the fx-series and the phenoms before have a simplicity to them that i admire. although i can't specifically say how or what it is.
Can you really call it innovation when AMD needs a 200W chip to compete with Intel's sub-100W chips? Unless you meant innovation in the high-tech space-heater market.
Intel has gone down the crank-clocks-power-be-damned path with Prescott about a decade ago and that did not work too well. AMD just tried the same thing and "shockingly," that did not work particularly well for them either.
What Gaurav Rai said:
"Meanwhile Amd innovates with 220W processsor XD"
Was humor. You know, like Ha-ha and stuff?
Even if you compare Sandy Bridge (32nm) Intel CPUs with AMD's FX83xx (28nm) which theoretically gives the advantage to AMD, Intel's older chips still win most benchmarks. Intel being one process node ahead has very little to do with their performance lead; their architecture itself is just that far ahead.
Hardly. Performance of the current Intel 4-core isn't that much better than the
equivalent model from 18 months ago. I know they've improved power consumption,
etc., but without significant speedups, most potential users really won't care.
Mike Stewart, you should be able to run your 2700K at 5.0. Every 2700K I've
obtained runs at 5 no problem, with good temps, etc.
OTOH, the chipset improvements with Z97 do at least offer a vaguely passable
rationale for upgrading, re the greater number of Intel SATA3 ports, newer
storage tech, etc. If budget was not an issue, I'd build with a 4790K without
hesitation.
Can't help feeling though, with various comments I've seen this past few weeks,
that what may be holding many people back from their ideal build is RAM pricing
which is now completely ridiculous. RAM is just too expensive. Huge step backwards
in system cost. And please I don't want to hear about chip shortages, etc., we all
know why RAM is more expensive now, because it's happened so many times before:
the suppliers don't like the pricing levels, so they restrict supply to raise prices. Well
IMO it's counter productive, because I can't be the only one who thinks no thanks,
I'm not paying that much for an 8GB 1600 kit when for about a 3rd less one could
get an 8GB 2133 kit a year+ ago, so heck with it I'll look for used kits instead, save
a bundle. I've bought four used GSkill 2x4GB 2133 kits this year, saved over 100 UKP
so far.
Price drops & efficiency improvements on CPUs are all fine & lovely, but what's the
point if potential future power savings are being wiped out by an artificially upfront
cost increase via the RAM?
Ian.
Which makes it all the more funny considering the Athlon XPs at the same time were more focused on efficient computing with better IPC instead of insane clock rates. You'd think AMD would have learned enough from that time not to fall into the Netburst trap.
Intel slides says >5% which mean over 5%.
[Edit: Thx, fixed!]
Hardly. Performance of the current Intel 4-core isn't that much better than the
equivalent model from 18 months ago. I know they've improved power consumption,
etc., but without significant speedups, most potential users really won't care.
Moore's Law states that the number of transistors on the chip will double every 24 months: http://en.wikipedia.org/wiki/Moore's_law
From the Wiki article: Moore's law is the observation that, over the history of computing hardware, the number of transistors in a dense integrated circuit doubles approximately every two years.
Double Transistors <> Double Performance (although early on it seemed that way)
Actually pitch means the space from the center of one fin to the center of the adjacent fin... it is not just the space between the 2 fins...
Back in those days, newer chips with more transistors were also on a smaller process, significantly higher clocks and usually accompanied with some fundamental performance enhancements/breakthroughs so the performance doubling every ~18 months was a combination of multiple compounding factors.
Today, practically all the fundamental discoveries have been made and all they are doing is refine them so that side of performance scaling is effectively shut down. The clock scaling also appears to have hit a brick wall since the latency hit from making pipelines longer to enable higher clocks causes the execution pipelines to stall on dependencies more often and negate gains from higher clocks. Process wise, they are at a point where they are starting to fight with fundamental laws of physics, which does not help with smooth progress either.
There is little reason to believe things are going to improve much any time soon when all aspects are well into their diminishing return curve.
Even if you compare Sandy Bridge (32nm) Intel CPUs with AMD's FX83xx (28nm) which theoretically gives the advantage to AMD, Intel's older chips still win most benchmarks. Intel being one process node ahead has very little to do with their performance lead; their architecture itself is just that far ahead.
FX-83xx series are 32mm, btw/fyi. fx-8350 vs. i7-2600k is probably a fair fight. i bet they'd trade blows. or, an fx-8350 is not far behind if it is behind. and amd has a software/platform/optimization disadvantage, meaning that the programs are not optimized for amd chips since most pc's have intel chips inside them.
Even if you compare Sandy Bridge (32nm) Intel CPUs with AMD's FX83xx (28nm) which theoretically gives the advantage to AMD, Intel's older chips still win most benchmarks. Intel being one process node ahead has very little to do with their performance lead; their architecture itself is just that far ahead.
FX-83xx series are 32mm, btw/fyi. fx-8350 vs. i7-2600k is probably a fair fight. i bet they'd trade blows. or, an fx-8350 is not far behind if it is behind. and amd has a software/platform/optimization disadvantage, meaning that the programs are not optimized for amd chips since most pc's have intel chips inside them.