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 Multi-Threaded Results
Looking at a multi-threaded run of Cinebench, the devices which will perform the best are going to need to have enough thermal headroom to keep all of the cores working at a good pace. All of these devices have four logical cores mapped to two physical cores via Hyperthreading, all of which are run at maximum load for the duration of this test.
The Core i5 once again has no issues maintaining its high CPU frequency, even though the overall SoC temperature does get higher than the single-threaded run. The Dell Venue 11 Pro tablet though starts off really reaching for the stars, but quickly must throttle back until it finds a consistent range that allows it to stay within its cooling constraints. The Yoga 3 Pro is similar, but quickly falls back due to the 65°C limit placed on the processor by the manufacturer. The ASUS UX305 performs just as well in this test as the last, with a very consistent CPU frequency, despite the temperatures getting a bit higher than the last run.
When it comes to average CPU frequency, both the Lenovo Yoga 3 Pro and the Dell Venue 11 Pro once again end up falling behind the ASUS and its much lower turbo speed in this test, though not by a huge margin. The ASUS averages the highest CPU frequency of the Core M contenders just like in the single-threaded workload, with the Lenovo less than 100MHz behind it, and the Dell Venue a ways back again. Neither of the 5Y71 devices turbo much over the 5Y10 in this test though.
Looking at the temperatures, you can see just how conservative Lenovo has been with the Yoga 3 Pro. The overall SoC temperature is quite a bit lower than all of the other devices when the device is under load. The active cooling and low SoC temperatures help the Yoga 3 Pro to keep a cool exterior to the device.
Now we come to the end result of this workload. The 5Y10 device handily outperforms both of the higher ranked models. Unsurprisingly it comes no where near the Core i5, but looking at the CPU frequency graph really demonstrates why it scores higher. Both of the 5Y71 have a lower average score, but unlike the single-threaded result, neither of them can sustain a CPU frequency past the frequency of the ASUS very much.
Facebook
Twitter
RSS
110 Comments
View All Comments
seapeople - Thursday, April 9, 2015 - link
Won't an over-aggressive turbo actually decrease performance? Processors are generally less power efficient at higher clock speeds, i.e., running at 3GHz is twice as fast as 1.5GHz but generally uses more than 2x the power, and thus more than 2x the heat.In this case, therefore, a processor that races to 3GHz will quickly (and less efficiently) use up its thermal headroom and have to throttle back moreso than a processor that stayed at 2GHz.
It's like a footrace - if the race is 100m long, you're going to finish fastest if you go all out. However, if the race is a mile long, then the guy who starts off sprinting is going to be sputtering along a quarter of the way into the race as the joggers pass him up.
MrSpadge - Friday, April 10, 2015 - link
You are right that with agressive Turbo the chip is running in a less power efficient state initially and will have to throttle a bit earlier than a slower, steadily running chip. but if we're talking about low performance under sustained loads, this doesn't matter: it affects the first few seconds, or 10's of seconds at most, whereas in the following minutes both systems are running at the same power efficient throttled speed, which is basically determined by the system cooling. It's not like the sprinter who's completely exhausted and can't recover.retrospooty - Wednesday, April 8, 2015 - link
I dont think its really all that complicated... If you are looking for raw performance, Core M isnt for you. It is really for low power devices that do basic stuff like browsing, email etc. For that purpose, its one hell of a CPU. That performance level at 4.5 watts is a hefty accomplishment IMOYuLeven - Wednesday, April 8, 2015 - link
I do development on a Core M machine. Instead of carrying 4 pounds of computing power on my back, I let a cloud based development box do the heavy lifting. The plume light Core M notebook is used basically to write the code and give orders to the Dev box. IMHO opinion a far better setup than having scoliosis for the sake of running code locally.mkozakewich - Wednesday, April 8, 2015 - link
It's not for web browsing. That's what Atom is for. A Core-M device is good for all regular core tasks except sustained graphics tasks. I wouldn't get one to game, but it'll be great for anything else.retrospooty - Thursday, April 9, 2015 - link
That is pretty much exactly what am saying. Basic use, core M is fine. Not for high performance requirements.nathanddrews - Wednesday, April 8, 2015 - link
They have taken the exact opposite approach to their SSD design, where they try very hard to offer constant and consistent performance.xthetenth - Wednesday, April 8, 2015 - link
Both make sense from the perspective of increasing perceived speed. With storage, it hanging and being slow is the biggest way it can impact the feel of the device, while processors that trade finishing short tasks much faster for a tiny decrease in how fast they complete long tasks do a lot to achieve a responsive feel.xthetenth - Wednesday, April 8, 2015 - link
Device buyers don't buy devices to get a higher average frequency, they buy things to do what they want without the device holding them up. Look at the benchmarks where the ASUS holds higher average frequencies but the Yoga's higher maximum frequency means it completes tasks faster, and it performs better in the benchmark. That sort of responsiveness is what turbo is for. The time to complete long tasks isn't going to be materially changed but the time to complete short tasks is going to be reduced significantly if the processor can use a quick burst like turbo allows.I'm also pretty sure that most users consider not getting burned by their device a good thing that should continue, incidentally.
StormyParis - Wednesday, April 8, 2015 - link
That's not a real use case though. Real use case is load a page (low CPU), render page (high CPU) read page (low CPU). I don't care how fast my CPU is idling while I'm reading the page, I do care how fast the page renders. It'd be different if I were running simulations.. that's what desktop CPUs are for.