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Intel's Core M Performance Is Erratic Between Devices
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."
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."
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.
Non impediti ratione cogitationus.
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.
const int one = 65536; (Silvermoon, Texture.cs)
SJW, n: "Someone I don't like, and by the way I'm a fuckwit" - AC
Turn it off.
Too bad they couldn't wait to integrate results from the single USB port MacBook. I'd be curious as to how well the new shell dissipates heat.
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.
Consider the source! Talk is cheap. And if you are "AMD" so is your shit CPU.
If you can't take the heat, get out of the laptop.
Some settling may occur during posting.
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.
This brings to mind the overheating issues with the early Apple III computers where heat would cause chips to expand out of their sockets, resulting in a system failure. Official Apple field solution? Lift computer 12 inches over a solid table/desk and drop! That would reseat the chips and the system could then be powered on and continue "normal" operations! I used to have a copy of that published "field expedient" - lost it in a move some years ago, though it may be in a box in my basement somewhere. Apple redesigned the heat sinks for the system (no fans involved, not including fanboys) to eliminate the problem, but by then, the Lisa, and soon the Mac, were out - the Apple III went nowhere fast!
The moral of this story is that heat control is critical for any computer system. Good systems have been designed to deal with it, fans or no fans.
When I used to overclock my CPU/GPU the first thing I did was crank up the fans to 100%. Never cooked anything, even at full load.
Heatsinks are the new superfluous luxury items.
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, and using Mac laptops as an example, why would I plunk down $1300 on a Macbook when I can put down $800-$900 on a Macbook Air, and buy better performance and battery life? Sure, the Macbook is thin and light, but isn't the Air already pretty damn thin and light? This question applies to other PC makers. Are other PC makers watching Apple to see if there is that strong a market demand for laptops that have better screen resolution, weigh less, and have slicker design but poorer specs overall? Do these questions make any sense?
There, I fixed the headline for you.
Once notebook computers became a fashion accessory that happens to compute, this result was inevitable.
Man, I got to use a PDP11 at my father's institute. I can assure you that lifting the machine would require industrial machinery. Also, the machine was rack-mounted with its disk... So that advice would not be very welcome :)
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 for user computers (as opposed to servers) is very much about perception. If your application opens snappily to begin with, the user will feel the computer is faster. If there is sufficient CPU power when you need it, it will have the same effect. It is all about balancing and making sure that your slower components are not needed as much as your faster components. Most users have CPUs sitting 85% idle most of the time..... getting a faster CPU only will increase the amount of idle time and not give the user a better experience.
The greatest performance boost in recent times is the advent and rapid improvement of the SSD. The stock CPU in many computers is increasing in performance in the single digits...... The majority of applications don't tax even the Core-M CPU (for the majority of users).
The word erratic in the title is misleading.
It should read something like: system performance determined by many factors in addition to CPU choice. No news here. Move along.
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 use than Yoga 3. In my usage, twice the battery of life or more of Yoga 3. Very light, sturdy and fast, great value. But also buggy graphic problems which seems to be Intel's Core M variant of the 5500 drivers. That plus I just missed backlight on keyboard, returned (but still a worthy model). HP Spectre x360. This unit is a bit heavier but in my view is the winner. Fast, excellent battery life, much better graphics driver, nicest keyboard in my experience. Due to a shipping error got the QuadHD screen, but surprised that unlike Yoga 3 Pro, battery life does not take much of hit and performance is much better. Really like it and it's a keeper. It feels fast enough if you want to do some Photoshop or medium editing but light and sturdy enough that it's close to Macbook Air functionality (3.26 lbs vs. 2.96). Nice range of models from non-Touch. I
Have fun with your slow ass MacBook after I warned you that their thermal solutions suck, ten thousand times.
Lol. Their year to year sales figures would not support your argument sir!
I thought they had changed their name?
Emphasis mine. Or does the skin part mean greater thermal conductivity?
Hello? Have everybody been sleeping during class?
So... why exactly do you need a PCIe SSD for watching videos again?
Because any above-average part that Apple includes is what makes their devices superior to the rest of the market, and anything they exclude or go for below-average on is superfluous, of course.
I remember sigs. Oh, a simpler time!
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 better yet, file a formal complaint for false advertising or fraud and then return them.
I blogged about this a while ago and I think the problem has only gotten worse. Lots of consumers are getting a crap experience because of insufficient cooling, manufacturers are selling rigs that can't do what they promise, and software developers waste time dealing with complaints about slow games/etc.
https://randomascii.wordpress....
I play games so I use a 8 core and dual video cards. The olde lady does Fakebook and email. A 8 year 4 core CPU and GPU does that for her the only change I did was use a SSD. Just for snicks I slowed a AMD 955 down to 1.8 Ghz and dropped Vcore down to see what power was needed. Would you believe 25 watts ? The onboard mobo video was using more power than the CPU, lol. This was before win 7 or 8. I don't believe it could run win7 or 8 very well. XP and Linux worked OK. I know where talking portable here. But it was running a 1080 monitor and could do general office software apps with reasonable speeds. Wake me up when 64 bit 3.0 ghz with 10 watts train TDP gets here please.
Sorry homer, not brainwashed, real world experience talking here.
Let's look at things, i7-3930k desktop(ivy-e not worth upgrading to) quad channel 1600 memory currently with ALL 10k mech hdds, although I am planning on switching the boot drive to an SSD when I get around to it. Anyways, the performance of this machine EASILY surpasses anything else I have, fx-9590(2133 mem dual channel), a10-7850k(2400 mem dual channel), i7-4770k(1600 mem dual channel), i7-4800mq(1600 mem dual channel), i7-4510U (8GB dual channel, but running 1x ATM), i3-4005U (can't remember mem specs ATM and I wouldn't be surprised if it got chopped to single channel as part of differentiation from i5/7), a celeron n2955u(haswell, dual channel, 1600 mem), atom z3735F(again don't recall if this one supports dual channel or not, but it is so low specced that it doesn't matter at all).
Using some cheapo benchmarks that I happen to recall the numbers for(chrome os people LOVE to use Octane v2 to benchmark, although I don't think it's that good of a benchmark):
i7-3930k 32k
i7-4770k 32k
i7-4800mq 32k
fx-9590 30k
a10-7850k 24k
i7-4510U 17k
i3-4005U 14k
I'm going to hazard an educated guess here that the topend core m 5y71 will probably max c. 7-8k octane.
Now in daily usage of the top 3: i7-3930k, i7-4770k, and i7-4800MQ there is a VERY significant difference in performance even amongst those three that one MIGHT think given similar/same octane bench scores would be about the same. It's not. They perform in other tasks as listed although the differences, e.g. compiling kernel, large excel spreadsheets, database ops, are a few minutes apart IIRC up to 10m for the i7-4800MQ but it may have been thermally throttled.
That said in the case of the i7-4800MQ I have TWO DISTINCT machines, one a 15.6"(1920x1080) paired with a 780m utilizing TWO SEPARATE HS/fan setups. The other is a 13.3"(again 1920x180) paired with 765m HOWEVER the two HS are heatpipe joined with a SINGLE fan -> thermal throttling under the right conditions, e.g. 100% CPU/GPU load, warm environment but that's the price of portability. When in more conducive conditions, not entirely loaded and cooler environment it just as functional as the 15.6" but more portable(which is why I bought as I knew of the thermal limitations of the design). The 15.6" rarely thermal thrtottles and that is generally in VERY WARM environments where HS/FA efficiency is reduced.
Moving on, we'll drop down to the two U parts, the i7-4510U and i3-4005U. Yes they're running two different OSes, but the i7-4510U's going on the auction block soon as I only purchased it for use in a project and getting OSX running on it on a lark. Bottom line here, even getting to the desktop of any OS the performance difference between even the U and the MQ parts(same parent architecture revision, haswell) IS MARKEDLY different. Even before loading it is ENTIRELY obvious that the U parts are just NOT nearly as capable as they are both thermally throttled AND TDP throttled. Perorming tasks similar to the desktops and i7-4800MQs the time differential runs into several 10s of minute MINIMUM and as much as a hour.
Core M WILL be even LOWER performing than these U parts, more aking to maybe i3/5 Y parts AND they are EVEN FURTHER TDP throttled AND THERMALLY limited. Both U machines have active fan/HS cooling similar to the 13" i7-4800MQ but NO discrete GPU to also handle.
Just go look at the anandtech article, e.g. the Dell 7140 CLEARLY has thermal design problems, while the Yoga 3 is apparently intentionally limited(by BIOS?) to lower operation frequencies/temps even though it DOES have active cooling.
I'll toss in an HP Probook 450-G1 i7-4710MQ that again linked HS/single fan setup(has amd 8750 discrete GPU IIRC never use it) to hackintosh, and again it was/is NOTICEABLY FASTER JUST BOOTING AND USING THE UI under OSX than the i7-4510U even.
So at the end of the day, ignore facts, keep on drinking the koolaid, believe the marketing schills, pay 10x what lowend is worth and have a nice day.