Analyzing Intel Core M Performance: How 5Y10 can beat 5Y71 & the OEMs' Dilemma
by Brett Howse & Ian Cutress on April 8, 2015 8:00 AM ESTCinebench R15 Single-Threaded Results
Cinebench will run the CPU up to 100% load for the duration of the test. As this is the single-threaded run, only one core will be active, which should in theory provide more headroom for that one core than when all cores (physical and virtual) are loaded. There is no burst workload here at all, and sustained single-threaded performance is the key for this test.
The Core i5 does exactly what would be expected for this benchmark. With just a single core loaded, the cooling system has no issues keeping the CPU from throttling. It maintains an extremely consistent CPU frequency during the run. This cannot be said of the two Core M-5Y71 devices though. The Dell Venue 11 Pro starts off with quite a high frequency, but as the temperature increases, the CPU drops in frequency to keep below the threshold of 90°C set on the SoC. At any opportunity, it increases its CPU frequency to try to increase performance, but generally that does not last for very long, and it ends up falling back down. The Yoga 3 Pro on the other hand, has a much lower allowed SoC temperature, with Lenovo locking in on 65°C as their maximum target temperature. This keeps the frequency down.
The ASUS Zenbook has an entirely flat CPU line though. The excellent heat dissipation of the chassis allows it to run for the duration of the benchmark with no throttling at all. It has to be noted though that the maximum CPU frequency is a quite a bit lower than the 5Y71 devices, topping out at 2.0 GHz versus 2.9 GHz for 5Y71. It would be very interesting to see how the UX305 would do with the faster CPU inside, and if it would run into throttling issues as well.
Looking at the average CPU frequency over the run shows that the i5 clearly has the most headroom, which is not surprising. Averages are only part of the story though, with both of the 5Y71 devices being able to jump past the 5Y10's frequency several times during the test.
Looking at temperatures, it's interesting to note that the Dell Venue 11 Pro has the top-tier Core M-5Y71, but it puts that processor in what is the smallest chassis and with a plastic exterior. Consequently it quickly loads up to its maximum temperature and stays there for the duration. The rest of the devices stay much cooler with just a single core loaded.
Here we have the actual benchmark results. On single-threaded workloads, the 5Y71 can and does outperform 5Y10. Despite the average CPU frequencies being lower on both 5Y71 devices, they had enough headroom when necessary to jump past the very consistent 5Y10. None of them can match the Core i5 in this test. It is actually very interesting that the highest scoring Core M in this test has the lowest average CPU frequency.
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maxxbot - Wednesday, April 8, 2015 - link
If the device buyer's choice is between the Core M and an ARM or Atom they're going to go with the Core M because it's faster in every aspect, especially burst performance. If the Core M in unacceptable slow for you then there aren't any other options at the 4.5W TDP level to turn to, it's the best currently available.name99 - Wednesday, April 8, 2015 - link
That ("Maybe Intel made too many compromises") seems like the wrong lesson.I think a better lesson is that the Clayton Christensen wheel of reincarnation has turned yet again.
There was a time more than 40 years ago when creating a computer was a demanding enough exercise that the only companies that could do it well were integrated top to bottom, forced to do everything from designing the CPU to the OS to the languages that ran on it.
The PC exploded this model as standardized interfaces allowed different vendors to supply the BIOS, the OS, the CPU, the motherboard, the storage, etc.
BUT as we push harder and harder against fundamental physics and what we want the devices to do, the abstractions of these "interfaces" start to impose serious costs. It's no longer good enough to just slap parts together and assume that the whole will work acceptably. We have seen this in mobile, with a gradual thinning out of the field there; but we're poised to see the same thing in PCs (at least in very mobile PCs which, sadly for the OEMs, is the most dynamic part of the business).
This also suggests that Apple's advantage is just going to keep climbing. Even as they use Intel chips like everyone else, they have a lot more control over the whole package, from precisely tweaked OS dynamics to exquisitely machined bodies that are that much more effective in heat dissipation. (And it gets even worse if they decide to switch to their own CPU+GPU SoC for OSX.)
It's interesting, in this context, where the higher frequency 1.2GHz part is difficult for some vendors to handle, to realize that Apple is offering a (Apple-only?) 1.3/2.9GHz option which, presumably, they believe they have embodied in a case that can handle its peak thermals and get useful work out of the extra speed boost.
HakkaH - Friday, April 10, 2015 - link
Device buyers don't even see beyond the price tag, brand name and looks. 90% of the people who buy tech are pretty oblivious on what they are buying. So they wouldn't even know if a device would throttle the speed at all.Secondly I'd rather have a device that throttles good which processors are doing the last couple of years than have a steady pace at which it just crawls along and maybe after 5 minutes decides... hey maybe I can add 200 MHz and still be okay. If that is your case I bet you still have the first generation smartphone in your pocket instead of a more recent model because they all aggressively throttle the CPU and GPU in order to keep you from throwing your phone out of your hands ;)
HP - Saturday, August 8, 2015 - link
Your description doesn't follow the usage paradigm of most computing tasks. As the user is actively using their device what they do on the machine roughly tracks the user's thought patterns which largely takes place in series. He doesn't batch the tasks in his head first and then execute them. So race to sleep is where it's at.milkod2001 - Wednesday, April 8, 2015 - link
What about Intel's native 4 core mobile CPUs. Are any in the works?Core M,Y, U(2 core) etc might be OK for bloggers, content consumers etc but if one wants/needs real performance on the go, there's not that much new to offer, right?
nathanddrews - Wednesday, April 8, 2015 - link
I think we'll have to settle for the i7-4700 until Skylake. Not a bad place to settle.kpkp - Wednesday, April 8, 2015 - link
"Atom competed against high powered ARM SoCs and fit in that mini-PC/tablet to sub 10-inch 2-in-1 area either running Android, Windows RT or the full Windows 8.1 in many of the devices on the market."Atom in Windows RT? Wasn't RT ARM only?
Essence_of_War - Wednesday, April 8, 2015 - link
Very impressed by the Zenbook, especially at its price point.boblozano - Wednesday, April 8, 2015 - link
Thanks for the detailed article.In this space it's clear that the top design consideration is cooling - do that well, and everything else follows. Performance will be delivered by the SoC's ability to turbo as needed, power consumption by the SoC and the rest of the design.
Of course materials, size, the question of passive vs. active cooling ... all that also factors decisively into the success of a design, whether the target market actually buys the devices.
But the effectiveness of the cooling will largely determine performance.
Refuge - Wednesday, April 8, 2015 - link
The efficiency of the cooling too. Can't have it take up too much space or too much power (If active and not passive)otherwise you leave either no room for your battery, or you drain it too fast keeping the thing cool (In the case of active)