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Intel Portables Hardware

Intel's Core M Performance Is Erratic Between Devices 85

An anonymous reader writes: AnandTech noticed some odd performance disparities with Intel's Core M CPU, a chip designed to bring high-powered processing to thin, fan-less devices. After investigating, they found that how OEMs build their laptops and tablets has a far greater effect on Core M performance than it does for other chips. "When an OEM designs a device for Core M, or any SoC for that matter, they have to consider construction and industrial design as well as overriding performance. ... This, broadly speaking, gives the OEM control over several components that are out of the hands of the processor designers. Screen size, thickness, industrial design, and skin temperature all have their limits, and adjusting those knobs opens the door to slower or faster Core M units, depending on what the company decides to target.

In the Core M units that we have tested at AnandTech so far this year, we have seen a variety of implementations with and without fans and in a variety of form factors. But the critical point of all of this comes down to how the OEM defines the SoC/skin temperature limitations of the device, and this ends up being why the low-end Core M-5Y10 can beat the high-end Core M-5Y71, and is a poignant part of our tests. Simply put, if the system with 5Y10 has a higher SoC/skin temperature, it can stay in its turbo mode for longer and can end up outperforming a 5Y71, leading to some of the unusual results we've seen so far."
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Intel's Core M Performance Is Erratic Between Devices

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  • by RyuuzakiTetsuya ( 195424 ) <taiki@c o x .net> on Friday April 10, 2015 @10:15AM (#49446119)

    It's something some of us Apple fans have long figured out is that individual specs sometimes are completely meaningless.

    Having a Core i7 will not actually feel more responsive in everyday tasks compared to a Core M if the i7 is paired with a spinning rust disk and the Core M has a PCI E SSD.

    Similarly, just looking at the chip in the machine might not tell us everything if we don't know anything about how it's handling cooling or what specific design choices were made.

    We're on the verge of reaching the 150HP car of computing. Don't really need much more for most tasks unless you're doing heavy lifting or looking to have fun, and even a lot of good clean fun can be had at 150HP.

    • by Anonymous Coward

      Pretty much any serious computer enthusiast knows this. Generally only tech illiterates fall for this when they buy the prebuilt computers at Best Buy and the like.

      • That or sales pitches as well, Ive noticed that most manufacturers wont give mention to what your putting their parts on. A top of the line graphics card wont do you much good if your motherboards chipset is past its prime. All the parts work together, no matter how you slice it, something is going to have to be the weakest point.

        • It will do fine in your example, as the graphics card is directly connected to the CPU's PCI express interface.
          The PC market is suprisingly free of rip offs these days, at least on the desktop side - and if you don't choose the low power CPUs while wanting something faster.
          Even there you don't suffer horrible bottlenecks like in the past (PIO mode hard drive, not enough RAM, omitted L2, then Intel graphics using up limited FSB and memory bandwith, then the first gens of Celeron Pentium 4 - all other Celeron

          • Comment removed based on user account deletion
            • by armanox ( 826486 )
              Another problem Apple is having is they lost a chunk of the people interested in their laptops with the nonsense they pulled with the Retina line where everything is soldered to the board.
            • Ferraris could do w/ better gas mileage, if not more speed
    • Re: (Score:1, Insightful)

      by lyovushka ( 4075741 )
      That's something some of Apple fans use to justify to themselves paying a premium for Apple products.
    • HDD is many orders of magnitude slower than SSD and quite a high latency, SSD is orders of magnitude slower than Memory, Memory is orders of magnitude slower than CPU cache etc. Getting a much faster CPU (GHz wise) does not increase the performance of the machine as much as many seem to be brainwashed into thinking. If you just upgrade a CPU with one 30% faster you will only get a fraction of that overall. It is all about having sufficient resources when you need them for the task at hand.

      Performance
    • by bill_mcgonigle ( 4333 ) * on Friday April 10, 2015 @01:06PM (#49447525) Homepage Journal

      Having a Core i7 will not actually feel more responsive in everyday tasks compared to a Core M if the i7 is paired with a spinning rust disk and the Core M has a PCI E SSD.

      Cool - I'll transcode a 900MB .dv clip to h.264 with ffmpeg on my 4-core hyperthreadding i7 (the low-power model, even) with a simple drive mirror, and you run it on your Core M with a PCIe SSD (on a Mac even), and let's see when each job finishes.

      (as usual, use the right tool for the task)

      • Number of people needing a machine capable of transcoding 900MB video clips is orders of magnitude smaller than the number of people watching videos. For a long time we made no distinction between content creators and content consumers. The content consumers were buying computers for more powerful than they need, and in that process lowered the cost of computing for content creators.

        Now those two groups are moving apart content creators (programmers, video/audio editors, web site creators etc) will have t

    • by LWATCDR ( 28044 )

      "It's something some of us Apple fans have long figured out is that individual specs sometimes are completely meaningless."
      No they are not.
      If you are transcoding video then a fast video card if using OpenCL or Cuda will really speed things up.
      If you are not then an I7 will really help.
      I love OS/X and I really like my macbook pro but the new iMac, Mac Book Pros, and Mac Pro are not as flexible as I want or need.
      SSDs are advancing too fast for me to not want the option of installing a new one. Apple charges t

      • I said sometimes and also referenced everyday tasks. Are you transcoding video on a daily basis?

        If you're a person who's transcoding video, then sure, one core i7 with less cores but higher frequency will do the job better than another core i7 with more cores and lower frequency.

        But if you're looking for a machine to do office suite docs, browse the web, email, etc. then comparing machines based on does this machine have a Core M vs Core M becomes irrelevant. You have to think about things like build qual

  • Nothng new (Score:4, Interesting)

    by AmiMoJo ( 196126 ) * on Friday April 10, 2015 @10:15AM (#49446123) Homepage Journal

    This has been the case for Intel CPUs for many years. Back in the Core 2 days they were already letting laptop manufacturers customize the power profiles (and therefore performance) of their mobile CPUs to suit the thermal load handling ability of their machines.

    If you have one of those old Core 2 machines and don't install the Intel chipset driver for it (or install the generic one) it will get hot and loud pretty quickly. The only real difference now is that the CPU has better management built in and works okay without the driver giving it hints.

  • by TyFoN ( 12980 ) on Friday April 10, 2015 @10:20AM (#49446169)

    I can't see any problem with that.
    Just read a few reviews before buying to make sure you get a device that is properly designed.

    • by Z00L00K ( 682162 )

      The problem is that the devices reviewed aren't the devices that you have available in the shops. Specifications and designs changes so fast that you can't keep up.

    • Notebookcheck [notebookcheck.net] is helpful in this regard. They test precisely how the thermal solution acts under maximum CPU/GPU load, in terms of temperature, noise and clock rate throttling.
  • If you can't take the heat, get out of the laptop.
  • Fantastic... (Score:5, Insightful)

    by fuzzyfuzzyfungus ( 1223518 ) on Friday April 10, 2015 @10:28AM (#49446247) Journal
    Intel model numbering has often been a bit cryptic, and worse more recently as they've spawned new product lines and taken advantage of their lead over AMD by market-segmenting with incredible precision, producing parts that differ by a single feature enabled or disabled, or have the same clock speed but different 'turbo' speeds, or any number of similar permutations.

    As though that isn't enough fun, now even expert level knowledge of the model numbers won't tell you how fast it is because the OEM can gimp it to suit their chassis design. It's a good thing that basically all modern CPUs are really fast, or this would be downright depressing.
  • I have noticed some wide disparities of performance in reviews of the new Macbook. One review I read put battery life at 7 hours, another at 11 hours of continuous video playback. Since there were no specifics, I don't know what to attribute these differences to. Who knew that the growth of mobile devices would direct manufacturers to focus on the design of the device? Intel's concern is now heat as much as power efficiency or performance. This point aside, if I were going to put down money for a new laptop
    • It may be as simple as how much a CPU/GPU is used in decoding the video stream (resolution / compression etc.). In addition the built in player is going to be more efficient than MPlayerX and VLC (I have noticed internal one can decode higher resolution videos on a machine than both of the others - I am guessing because of use of GPU or something).
    • There are a number of things that could conceivably alter the results between tests of similar machines, such as ambient temperature, the specific video codec used for movie playback (some are more CPU intensive than others), whether the video was being streamed from the HD or streaming wirelessly (wireless radios suck up a lot of power), the screen brightness, and so on. I'd simply look at the range of numbers as best and worst case scenarios that you're likely to see.

      I can't answer any of your other ques

  • by QuietLagoon ( 813062 ) on Friday April 10, 2015 @11:20AM (#49446627)
    There, I fixed the headline for you.
  • Fashion accessory (Score:5, Insightful)

    by QuietLagoon ( 813062 ) on Friday April 10, 2015 @11:36AM (#49446737)
    Once notebook computers became a fashion accessory that happens to compute, this result was inevitable.
  • by ITRambo ( 1467509 ) on Friday April 10, 2015 @12:55PM (#49447443)
    Of the two systems that performed best with the bottom of the line Core M, one used a cooling fan while the other had an aluminum shell that acted as a heat sink. The machine with faster processor had a plastic shell with no active cooling. It throttled back when it got warm and would not run at full speed due to heat buildup. Hence the reason why a lower power CPU outperformed a higher powered one. Shell design is everything when it comes to quickly venting heat. Don't use enclosed plastic if you need to cool a CPU that is designed to run at 65C. Use a metal shell, or an active cooling system if the shell is plastic.
  • I just lived this - I started with a Dell Venue Pro 11 i5, TDP 11.5W in plastic case. It was a throttling and heat nightmare, slow, sluggish, very buggy graphics drivers. Next up was the Yoga 3 Pro in the review. Saw the same performance oddities in the review plus buggy graphics (frequent crashes with video, flash, very poor windowed video performance) and poor battery life despite removing all bloatware. Moved to a Asus Zenbook UX305 in the review, Signature Model sold by Microsoft. Felt much faster in
  • Have fun with your slow ass MacBook after I warned you that their thermal solutions suck, ten thousand times.
  • If a buy a computer with a CPU that is rated at X GHz then that CPU had better be able to maintain that frequency, always. Otherwise it's a meaningless number. CPUs can already overclock themselves (Turboboost) above that frequency so if they can also legitimately underclock themselves then the 'rated frequency' is completely meaningless. I don't think that is acceptable. I encourage all slashdot readers to test their new computers under load and if they cannot maintain their rated frequency RETURN THEM! Or

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