Performance: Atom vs. ARM's Cortex A15

In our iPhone 5 review I included this crude diagram comparing the high level micro-architecture layouts of the current crop of mobile CPU cores. While most of the cores looked fairly similar, the one to really stand out is ARM's Cortex A15. A three issue, OoO core, the Cortex A15 was designed to put ARM in a completely new performance category.


For 2013, the Cortex A15 is expected to be the ARM CPU core of choice for the next wave of smartphone and tablet SoCs. NVIDIA's Wayne should integrate multiple Cortex A15s as well as competing solutions from Samsung and TI. Samsung's Exynos 5 Dual, found in the new Chromebook, integrates two ARM Cortex A15 cores running at 1.7GHz. As our first experience with a Cortex A15, I wanted to get a good idea for how it would compare to Intel's Atom. And now me comparing to the older Chromebook 500 makes sense. The Atom N570 in the older Chromebook is the closest approximation we have to the currently shipping Atom based mobile SoCs. There are a number of enhancements to the newer chips (particularly when it comes to power consumption), but the base core is very similar. It's clear that the Sandy Bridge Celeron based Chromebook is faster than this new Cortex A15 design, but how about the old dual-core Atom model?

As Chrome OS is built around the Chrome browser, our tests had to be largely JavaScript based unfortunately. The good news is that even given the nature of the benchmarks, we're able to get a good feel for performance between the two SoC platforms. Both systems were running the latest version of Chrome OS at the time of publishing.

Samsung Chromebook Performance Comparison
  SunSpider 0.9.1 BrowserMark RIABench Focus Tests Kraken
Atom N570 1.66GHz 1034.3 ms 152780 1968 ms 14229.5 ms
Exynos 5 Dual 1.7GHz 690.5 ms 217031 1192 ms 9733.2 ms

The Cortex A15 is fast. Across the board we're seeing a 40 - 65% increase in performance over a dual-core Atom. Although it's not clear how performance will be impacted as companies work to stick Cortex A15 based SoCs in smartphones with tighter power/thermal budgets, in notebooks (and perhaps even tablets) the Cortex A15 looks capable of delivering a good 1 - 2 generation boost over Intel's original Atom core.

The IE10 browser tests tend to agree with our JavaScript performance tests, although the CSS Maze Solver benchmark shows a huge advantage for ARM over Intel's Atom here.

Samsung Chromebook Performance Comparison
  IE10 Bubbles Test IE10 Fishbowl IE10 Maze Solver
Atom N570 1.66GHz 11 fps 5 fps 45 seconds
Exynos 5 Dual 1.7GHz 17 fps 8 fps 17 seconds

GPU performance is an even bigger advantage for the Exynos 5 Dual over Intel's old Atom N570 (GMA-3150 GPU). I ran three different webGL tests, each of which showed just how bad the old Atom GPU core was.

Samsung Chromebook GPU Performance Comparison
  WebGL Solar System WebGL Cubes (500) WebGL Aquarium (50)
Atom N570 1.66GHz 2 fps 10 fps 2 fps
Exynos 5 Dual 1.7GHz 22 fps 28 fps 38 fps

This comparison isn't really all that fair as the newer Atom cores use Imagination GPUs, although even then they are using relatively underpowered solutions compared to what Samsung is shipping on the Exynos 5 Dual.

The more relevant conclusions here apply to the CPU comparison. Next year Intel is expected to introduce its first new Atom core since the platform's introduction five years ago. The new architecture will bring an Out of Order execution core as well as a tangible performance increase. The question is whether or not this will be enough to fend off advances from Cortex A15 based designs.


The new Chromebook (left) vs. the old Atom based Chromebook (right)

In our Surface review I looked at Clovertrail Windows 8 tablet performance and put it a good 40%+ faster than NVIDIA's Tegra 3. If ARM's Cortex A15 is able to outperform Clovertrail by a similar margin, it could make the next generation of Windows RT tablets even more attractive. Keep in mind that we're looking at an older Atom platform here and not Clovertrail, so the performance deltas could shrink a bit.

User Experience & Usability Battery Life & Power Analysis
POST A COMMENT

149 Comments

View All Comments

  • actionjksn - Thursday, November 08, 2012 - link

    How would the performance on this compare to a similarly clocked Core 2 Duo? I'm talking about CPU tasks not graphics. Reply
  • TheJian - Monday, November 12, 2012 - link

    You're forgetting to mention your basing that on a 1.3Ghz cpu from a year ago instead of the 1.7ghz tegra3+ that they're currently putting out (htc one x+ etc). That's about another ~27% you're leaving off NV's table right anand?

    So Intel's current tech is just about to catch NV's old tech with Tegra4 just around the block that will increase cpu (I don't expect much here, but they don't need much already quad and performs on par with what just came out to a large degree), and double gpu since going quad instead of dual, so at worst it will double if no chip improvement at all, and dual channel finally. Looks like they'll be behind again just after launch I guess? They'll have to do better than catching last years tech. And they didn't make it into xmas devices like Tegra. So again NV will get their tech out in time in Q1 for craploads of devices to be planned all year. I'm thinking it's best to be fastest in March/April if you want to be designed into Xmas devices.

    Surface may have chosen the 1.3ghz but they should have ran a 1.7ghz Tegra3+. I guess it saved them $10/surface (less?). I'm sure customers would rather pay $5-10 for another 30% performance. They should at least offer the option. Oh well. I told my dad to buy a Nexus 10 for xmas anyway and I'll wait for a great 10in Tegra4 as if I'm going to game (dad isn't much) I want Tegra game optimizations and everything out now isn't quite as good as I'd like for Xbox360 portable replacement and double as a laptop i9300 replacement (it's 8yrs old...LOL). Nvidia seems to be the only one helping devs make some great stuff and gaining praise from the likes of Carmack and Epic's Unreal team.
    Tegrazone.com has some great games in the pipe. I'm looking forward to Baldurs Gate enhanced on a 65in TV in the near future too...LOL. That game should run on anything out by everyone on the top end and give gamers a good 100+hrs of fun on the bigscreen without an xbox360/ps3. With my limited game time, it should hold me over until android gaming really takes off. There are 5 unreal 3 engine games in the pipe now, and lots of other good looking stuff at tegrazone says next xmas should be excellent. I'm sure Id's engine will get used by them in a few games also. Between these and my PC I should have no reason to even look at an xbox720/ps4. I'm guessing a lot will be in the same boat.

    I may have to pony up for the cube u30gt jelly bean to get me to xmas which should produce a tegra4+. Then again going from 40nm to 20nm there may be no need. That's a HUGE decrease in chip size and samsung is better than TSMC at any process. The U30GT (and it's ilk) look pretty dang good for $200 tablet at 10in for something to use for training vids/books etc until next year.
    Reply
  • sathish2020 - Wednesday, November 21, 2012 - link

    "With Apple pushing at the top and Google working the bottom" Nice one. Reply
  • deslock - Thursday, November 29, 2012 - link

    Thanks for the detailed (as usual) review. A question:

    Since it idles at 6.33W and has a 30 Watt-hour battery, shouldn't it last less than 5 hours with the screen on? It lasted 6.07 hours in the browsing test.
    Reply
  • ramonchis - Thursday, January 10, 2013 - link

    Hi. I got one of these a couple of days ago. In the first day I broke the LCD by putting some weight on the laptop.

    I went to the store (Best Buy) to check if they could repair it of exchange it, but they did not offer any solutions.

    So.... I would like to change the screen myself, which I have done in the past with other laptops.

    Did you get a chance to open the screen lid? Do you know the LCD model?

    Thanks!
    Reply
  • calden - Sunday, January 27, 2013 - link

    I have used the Chromebook Since the CR-48 then moved to the Acer and now this one. You will be surprised as to how useful the apps found in the Google store really are. I use Microsofts 365 and I am just as productive as if I was using the full program on a normal laptop. I recently found a new online service called Lime Documents, fantastic. The writing program is called Lime Writer and after using it I can honestly say I will never have any use for none web apps again. www.live-documents.com/live_writer.html The same goes for the Excel and Powerpoint clone, there awesome apps.

    I love having the security the Chromebooks give me, I travel a lot and have either have had my laptop stolen or lost after a night of drinking. These give me the freedom of just shrugging my shoulders and saying oops instead of freaking out that someone now has photos of me and my dog with peanut butter. That was a joke of course it was the cat, at 250 dollars though these really are disposable computers.

    My company recently bought over 300 Chromeboxes and Chromebooks. Our company is an all Unix environment with 90 percent of our data and internal apps being served from Oracle, in which all info is displayed with web apps. The few people who need Office or other software like the treasury department can display them using Citrix. A feature that was left out of the article, I for one use a CRM program called Goldmine. When I travel the 4G connection I have is more then fast enough to display this program and others. The Chromeboxes make a perfect dumb terminal, their also priced much better then the HP solution we were using. Google also doesn't mess about, we have many spares to switch out the defective ones if nessecsary. We then send them back to Google who just gives us new ones.

    To tell you how useful a web program can be our software development team uses online development apps that were found in the Google store. They claim it's as good as if they were using Eclipse or Netbeans. I was actually amazed when they showed me. It's also a good employee incentive to give out a laptop to everyone even the secretaries. Yes they are just Chromebooks but our staff really seems to enjoy them as they can't muck'em up like they can with ordinary machines. We supply our people with Samsung 550's, the ARM version was deemed to slow but I took ome of the evaluation machines for my self as I like the size. I find it to be quick enough for my needs, I can stream 1080p movies from my Google Drive account without breaking a sweat so it's just fine for my needs.
    Reply
  • qwerty321 - Wednesday, March 20, 2013 - link

    One of the guys working at Linaro claims he has the USB 3.0 port pushing 70+ MB/s. I'm guessing an engineer knows better than a laypress hack. Reply
  • EvilTed - Saturday, September 07, 2013 - link

    He should enlighten everyone how?
    I call BS on your enlightened engineers claims!

    I'm fuming mad at Samsung for blatant false advertising.
    I have tried ChromeOS as well as Ubuntu with Unity and XFCE and the average throughput over USB 3.0 is 16MB/s, which is slower than my 2011 Mackbook Pro over USB 2.0 :(

    I actually bought my Chromebook for image transfer and storage from SD card to USB 3 drive.
    The fact it cannot produce at all has left me with a $250 doorstop.

    Class action suit anyone?

    ET
    Reply

Log in

Don't have an account? Sign up now