The iPhone 6 Review
by Joshua Ho, Brandon Chester, Chris Heinonen & Ryan Smith on September 30, 2014 8:01 AM EST- Posted in
- Smartphones
- Apple
- Mobile
- iPhone 6
A8: Apple’s First 20nm SoC
As has been customary for every iPhone launch since the company began publicly naming their SoCs, Apple has once again rolled out a new SoC for their latest line of phones. With the launch of the iPhone 6 series Apple is now up to their eight generation SoC, the appropriately named A8.
After a period of rapid change with the A6 and A7 SoCs – which introduced Apple’s first custom CPU design (Swift) and the first ARMv8 AArch64 design (Cyclone) respectively – A8 is a more structured and straightforward evolution of Apple’s SoC designs. Which is not to say that Apple hasn’t been busy tweaking their designs to extract ever-improved performance and power efficiency, as we’ll see, but our examination of A8 has not uncovered the same kind of radical changes that defined A6 and A7.
The heart and soul of A8 is as always the CPU and GPU. We’ll be taking a look at each of these individually in a moment, but from a high level both of these are evolutions of their predecessors found in A7. Apple’s GPU of choice remains Imagination’s PowerVR, having upgraded from the Series6 based G6430 to Imagination’s newer GX6450 design. Meanwhile Apple continues to develop their own CPUs and A8 packs their latest design, which is an enhanced version of the Cyclone core first introduced in A7.
Stepping away from the GPU and CPU for the moment, the biggest change about A8 is that it’s smaller. As discovered by Chipworks, A8 is being fabricated on TSMC’s new 20nm process, making the iPhone 6 among the first smartphones to be shipped with a 20nm SoC.
This move to 20nm is not unexpected, but nonetheless it is considerable for a couple of reasons. The first is that this means Apple has moved production over to TSMC’s 20nm HKMG Planar process, making this the first time an Apple SoC has been manufactured anywhere but a Samsung fab. There are numerous possible reasons for this – and not every reason needs to be technical – but from a process development standpoint it’s important to note that over the last few generations TSMC has been the leader among contract foundries, being the first to get new processes up and running for volume production.
| Apple A8 vs A7 SoCs | ||||
| Apple A8 (2014) | Apple A7 (2013) | |||
| Manufacturing Process | TSMC 20nm HKMG | Samsung 28nm HKMG | ||
| Die Size | 89mm2 | 102mm2 | ||
| Transistor Count | ~2B | "Over 1B" | ||
| CPU | 2 x Apple Enhanced Cyclone ARMv8 64-bit cores |
2 x Apple Cyclone ARMv8 64-bit cores |
||
| GPU | IMG PowerVR GX6450 | IMG PowerVR G6430 | ||
This move is also quite considerable because it means for the first time Apple is manufacturing their SoCs on a bleeding edge manufacturing process. Prior to this Apple has been slow to utilize new manufacturing processes, only finally utilizing a 28nm process in late 2013 for A7 over a year after 28nm first became available. The fact that we are seeing a 20nm SoC from Apple at a time when almost everyone else is still on 28nm indicates just how much the market has shifted over the last few years, and how Apple’s SoC development is now synchronized with the very edge of semiconductor fabrication technology.
Finally, the switch to 20nm is interesting because after the last couple of generations being so-called “half node” jumps – 45nm to 40nm to 32nm to 28nm – the jump from 28nm to 20nm is a full node jump (note that Apple didn't ever use 40nm, however). This means we are seeing a larger increase in transistor density than in the previous generations, and ideally a larger decrease in power consumption as well.
In practice TSMC’s 20nm process is going to be a mixed bag; it can offer 30% higher speeds, 1.9x the density, or 25% less power consumption than their 28nm process, but not all three at once. In particular power consumption and speeds will be directly opposed, so any use of higher clock speeds will eat into power consumption improvements. This of course gets murkier once we’re comparing TSMC to Samsung, but the principle of clock speed/power tradeoffs remains the same regardless.
Not accounting for minor differences between TSMC and Samsung, in an ideal case Apple is looking at 51% area scaling (the same design on 20nm can be no smaller than 51% of the die area at 28nm). In reality, nothing ever scales perfectly so the density gains will depend on the kind of I/C being laid down (logic, SRAM, etc.). For the complete chip a 60-70% scaling factor is going to be a better approximation, which for Apple means they’ve picked up a lot room to spend on new functionality and reducing their overall die size.
| Apple SoC Evolution | |||||
| CPU Perf | GPU Perf | Die Size | Transistors | Process | |
| A5 | ~13x | ~20x | 122m2 | <1B | 45nm |
| A6 | ~26x | ~34x | 97mm2 | <1B | 32nm |
| A7 | 40x | 56x | 102mm2 | >1B | 28nm |
| A8 | 50x | 84x | 89mm2 | ~2B | 20nm |
Meanwhile once again this year Apple opened up on die size and transistor counts. A8 weighs in at around 2 billion transistors, as opposed to the “over 1 billion” transistors found on A7. We also have the die size for A8 – 89mm2 – which is some 13% smaller than A7’s 102mm2 die. This makes it clear that Apple has chosen to split their transistor density improvements between adding features/performance and reducing their size, rather than going all-in on either direction.
In the case of using a bleeding edge node this is generally a good call, as Apple and TSMC will need to deal with the fact that chip yields at 20nm will not be as good as they are on the highly mature 28nm process. With lower chip yields, a smaller die will offset some of those yield losses by reducing the number of manufacturing flaws any given die touches, improving the overall yield.
A8 With POP RAM Removed
Moving on, looking at A8 we can see that Apple’s memory subsystem design has not significantly changed from A7. Once again Apple has placed an SRAM cache on the chip to service both the CPU and the GPU. Based on an examination of the die and of latency numbers, this L3 SRAM cache remains unchanged from A7 at 4MB. Meanwhile we also find a series of SDRAM interfaces which drive the A8’s package-on-package (POP) based main memory. Based on teardowns from iFixit, Apple is using 1GB of LPDDR3-1600, the same speed grade of LPDDR3 and capacity that they used for the iPhone 5s. iFixit has found both Hynix and Elpida memory in their phones, so Apple is once again using multiple sources for their RAM.
When we start poking at memory bandwidth we find that memory bandwidths are consistently higher than on A7, but only ever so slightly. This points to Apple having worked out further optimizations to make better use of the memory bandwidth they have available, since as we’ve previously determined they’re still using LPDDR3-1600 speeds.
| Geekbench 3 Memory Bandwidth Comparison (1 thread) | ||||||
| Stream Copy | Stream Scale | Stream Add | Stream Triad | |||
| Apple A8 1.4GHz | 9.08 GB/s | 5.37 GB/s | 5.76 GB/s | 5.78 GB/s | ||
| Apple A7 1.3GHz | 8.34 GB/s | 5.21 GB/s | 5.67 GB/s | 5.69 GB/s | ||
| A8 Advantage | 9% | 3% | 2% | 2% | ||
The Stream Copy score ends up being the biggest gain at 9%. Otherwise the rest of the benchmarks only show 2-3% memory bandwidth increases.
More interesting is memory latency, which shows some unexpected improvements once we get out of the L1 and L2 caches. At both the 1MB – 4MB region of the SRAM and 6MB+ region of main memory, memory latency is consistently lower on A8 versus A7. In both cases we’re looking at latencies about 20ns faster than A7. This identical 20ns gain tells us that that Apple is still doing main memory lookups after the L3 lookup fails, and this in turn means the 20ns gain we’re seeing is due to L3 cache optimizations. We have a couple of ideas for how Apple could have improved L3 latency by nearly 20% like this, but at this time with Apple staying quiet on their architecture like usual, it’s not apparent which of these ideas are the correct ones.
Turning our eyes back to A8 one final time, we find that while a lot of die space is occupied by the CPU, GPU, and SRAM (as we’d expect), there is also quite a bit of space occupied by other blocks Apple has integrated into their design. Without already knowing what you’re looking for these blocks are difficult to identify, but even without being able to do this we have a reasonable idea of what blocks Apple has integrated. Among these we’ll find audio controllers, USB controllers, video encoders/decoders, flash memory controllers, the camera ISP, and of course all kinds of interconnect.
All of these blocks are fixed function hardware (or at best, limited flexibility DSPs), which are equally important to not only the A8’s functionality but power efficiency. By assigning tasks to dedicated hardware Apple does spend some die space on that hardware, but in return these blocks are more efficient than doing those tasks entirely in software. Hence Apple (and SoC designers in general) have a strong incentive to offload as much work as possible to keep power consumption in check. This move towards more fixed function hardware is part of a general “wheel of reincarnation” cycle that has been a constant in processor design over the years, which sees a continuous shift between fixed function and programmable hardware. SoCs, for the most part, are still going towards fixed function hardware, and this should continue for a while yet.
In any case, while we can’t identify individual blocks on A8 we do know that Apple has added a few features to A8 that are present in some form or another among these blocks. New to A8 is some mix of H.265 (HEVC) hardware, which would be necessary to enable the FaceTime over H.265 functionality that is being introduced on the iPhone 6. Apple’s “desktop class scaler” that is used for handling non-native resolution applications and for down-sampling the internal rendering resolution of the iPhone 6 Plus would also be present here.
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dingodingaling - Thursday, October 2, 2014 - link
1. Is there circumstantial evidence to suggest that AnandTech are Apple Stooges?Yes, absolutely. The founder and owner of the site works for Apple and so does one of their long term “reporters”.
2. Were AnandTech motivated to be Apple Stooges?
Yes, absolutely.
AnandTech are a commercial website, funded by advertising dollars. It is in their interests to drive up traffic and views of their site.
They know that:
a. iPhone users trawl every site that says anything in advance of an iPhone launch to pick up rumours, and after the launch to view “reviews” that help them avoid cognitive dissonance.
b. Apple punish negative reviews by withdrawing access to review devices and invitations to events. http://www.cultofmac.com/255618/how-apples-blackli...
http://www.zdnet.com/blog/apple/apple-prs-dirty-li...
c. Being punished like this will impact them severely from a commercial perspective. They are therefore commercially incentivised to have positive reviews.
3. What means could they use to be Apple Stooges?
Given we know they are motivated and incentivised to give Apple products good reviews, we can analyse how they do it. This can be in 5 basic ways:
a. Use the Apple provided product, not one they brought off the shelf, meaning Apple can tune that one device for tests;
b. Cherry pick tests where the Apple product will do well, and ignore those that they don’t;
c. Carefully select the “comparison” devices, ignoring any that make Apple devices look bad;
d. Make up tests where they think they need to cover up a hole, but ensure that no one else knows how the test works so they can’t repeat it, and
e. Make “mistakes” occasionally and assume no one will notice.
4. Is there evidence to suggest they are using these methods?
a. Use the Apple provided product, not one brought from a store randomly.
Yes we know they do this, and they admit it. Also looking at the Display tests there is evidence to suggest that the Apple provided product was tuned. They themselves had to admit their suspicions.
b. Cherry picking tests.
Yes, they do this.
3DMark Ice Storm
“On the synthetic benchmark 3DMark Ice Storm Unlimited, the iPhone 6 Plus scored 16,965. While that's well above the category average of 13,401, it fell below its Android competition. The S5 blew past with a score of 18,204, as did the HTC One M8 (20,640), the LG G3 (17,548), the OnePlus One (18,399) and the Note 3 (18,321)”
http://www.laptopmag.com/reviews/smartphones/apple...
CNet finds similar results
<image001.jpg>
http://www.cnet.com/products/apple-iphone-6/
An example from Arstechnica
<image002.png>
More results at:
http://results.rightware.com/basemark_x/all-all-ph...
The Stooges select some of their tests (“Basemark X) but not others – why is that??
c. Carefully select the “comparison” devices, ignoring any that make Apple devices look bad;
Yes, they do this.
For the display, the comparisons for max brightness is missing phones for example the Note III which Tom’s hardware measure at 555 Nits. Why the missing phones?? Surely the Stooges have tested these.
One of the missing phones is the Note IV which displaymate tested and rated as the best Smartphone display – and their testing includes both iBends.
“The Best Performing Smartphone or Phablet Display that we have ever tested.”
http://www.displaymate.com/Galaxy_Note4_ShootOut_1...
http://www.displaymate.com/Galaxy_Note4_ShootOut_1...
Suspicious that its missing!
For contrast where are phones like the Galaxy S5? This comparison shows that the S5 has amazing contrast.http://www.phonearena.com/reviews/Apple-iPhone-6-v...
d. Make up tests where they think they need to cover up a hole, but ensure that no one else knows how the test works so they can’t repeat it
Yes, they do this.
For battery Life their test is simply wacko – the only site that has the iBends winning battery life tests and probably due to the rigged nature of the “web browsing” test.
http://gfxbench.com/result.jsp?benchmark=gfx30&...
Tom’s hardware has also has completely different results to the Stooges for battery life and web-browsing http://www.tomsguide.com/us/iphone-6-battery-life,...
Phonearena also have ‘web browsing’ tests that show the iBends aren’t great
http://www.phonearena.com/news/All-bow-to-the-new-...
Arstechnica also found the Ibend battery life to be average.
http://arstechnica.com/apple/2014/09/iphone-6-and-...
e. Make “mistakes” occasionally and assume no one will notice.
Yes, they do this.
Sunspider
The iBend6+ has better measurements than on Tom’s Hardware.
Geekbench 3
The iBend6+ has worse scores on Tom’s hardware than the Galaxy S5 and Note III.
GFXBench 3.0 Manhatten Offscreen
Stooges are rating the IBend6 and iBend6+ higher than GFXBench themselves have tested it at.
http://gfxbench.com/result.jsp
http://laptopmag.com/reviews/smartphones/apple-iph...
The measurement for the iBend6+ is different on Tom’s hardware (its better!), but also different for all the other phones.
More “mistakes” for the colour temperature and gray scale accuracy are completely different in that test as well.
.http://www.phonearena.com/reviews/Apple-iPhone-6-v...
vFunct - Thursday, October 2, 2014 - link
Give it up.Your Android phones area garbage. They're fake iPhones. Apple invented the modern smartphone, and all the innovations like Retina displays. Android keeps trying to copy Apple, but they're never as good or as fast.
Why get a fake iPhone when you can get a real iPhone instead?
Fake iPhones are terrible. Get a real iPhone instead.
KuyaMarkEduard - Sunday, October 5, 2014 - link
Hello Dingodingaling. Are you certain that this practice of Apple is still existing even today, as we speak?""Apple PR's dirty little secret:
Summary: Apple PR maintains a blacklist of journalists that it refuses to talk to. This includes any media outlet that posts anything even remotely negative or heaven help you, a rumor.
Apple's public relations department is notoriously tight-lipped and only responds to a limited subset of the mainstream media, and usually only the outlets that write positive things about its products.
If you dare to write an unflattering piece about Apple or -- heaven forbid -- post a rumor you're almost guaranteed to lose your access to Apple. I know this firsthand because I'm the poster child of Apple's PR blacklist. (I was part of a precedent-setting legal case with Apple in 2005, which I won on appeal in 2007 -- thanks to the Electronic Frontier Foundation.)
Say what you will about my work, but I call 'em like I see 'em.
I write good things about Apple, I write bad things about Apple and I also publish rumors when I believe that they're credible or plausible. I write about things that I find interesting and about topics that will benefit my readers. Sometimes Apple likes what I write other times it doesn't. Apple and I have classic love/hate relationship.
But one thing's for sure, I'm not an Apple cheerleader. If like reading puff pieces about Apple there are a number of websites and blogs that will gladly oblige. Or heck, just dial up apple.com/pr.
Case in point: On February 7 when Arun Thampi posted on his blog that Path was sneakily uploading iPhone user's address books to its server -- without permission -- I called and emailed Apple. Apple didn't reply. Then and I blogged about it.
On February 8 when Dustin Curtis blogged that Apple makes a standard practice of approving apps that upload the entire contents of your iOS address book to developer’s servers I again called and emailed Apple. Apple didn't reply. Then I blogged about it.
Later. Rinse. Repeat.
Then I got an idea. Since Apple PR never responds to my voicemails or emails, maybe they'd respond to the guys that do have access. So I contacted several prominent Apple pundits (who shall remain nameless) that are known for their access to Apple (some of whom get replies from Apple "every time") and I asked them to enquire about Apple's stance on enforcing its policy on address book uploads.
And you know what? None of them would do it.
(Update: ironically there's a couple of exclusive stories out today about Mac OS 10.8/Mountain Lion which certain members of the Mac Illuminati had access to a week early.)
Why? They'd probably say that Apple wouldn't comment. But someone's got to ask if they expect Apple to reply. I mean come on! Apple's not going to press release its shady developers that steal your contacts.
The fact of the matter is that most journos with access to Apple are afraid of losing it. They're afraid of asking the tough questions. They're afraid of getting blacklisted. Like me.
So then I contacted the Wall Street Journal.
There's a prominent columnist at WSJ that has lots of access to Apple. Arguably the most access to Apple. Apple loves the Journal. Apple sends controlled leaks to the Journal. Apple gives unreleased product to the Journal. Surely, Apple would have to respond to the Journal. Right?
Well guess what? Apple spokesman Tom Neumayr replied to AllThings today about the issue of developers stealing your contacts without permission. (More on that later)
Gee? I wonder why?
I'll tell you: AllThingsD is a wholly owned subsidiary of Dow Jones & Company Inc., which is a member of The Wall Street Journal’s Digital Network (which includes WSJ.com, MarketWatch, Barron's, and SmartMoney).
It's simple really. Apple needs the Journal. The Journal doesn't need Apple. And the Journal's not afraid of getting on Apple's PR blacklist -- because it would never happen.
Other wags with access, but without the clout of the Journal are probably afraid of getting blacklisted if they probe around too much -- or ask the tough questions.
My point is that if Apple PR actually read blogs and responded to queries from bloggers things like Address-gate might not explode into giant issues that end up in the Wall Street Journal. Apple could have nipped it in the bud a week sooner by simply replying to my email or voicemail with something to the effect of "yes, we're aware of the issue and we're looking into it."
Instead, Apple makes a conscious point of ignoring certain journalists hoping that unsavory issues like Address-gate blow over and that no one will notice. Well guess what, I'm persistent. And if Apple doesn't reply, I'll contact the people that I know at the Journal -- or my Congressman.
And before you cry "sour grapes!" consider this. I've been blacklisted by Apple for over 10 years. I never get invited, I never get replies. I'm long over it. This doesn't have anything to do with me. It's about you and your privacy. I called and emailed Apple PR because I care about my (and your) private contacts and I wanted to know why Apple isn't enforcing its own privacy policies.
If you don't care about developers stealing your contacts, that's fine. But I do.""
Because if so, with the iBend issue, how can now then we be assured that each and every-time Apple will say a thing about the issue, will always be true, and not fabricated?
This is indeed, an eye-opener to all the Serious tech-readers out-there…, …Of-course, this does-not include the Fanboys.
EricGee - Friday, October 3, 2014 - link
If both new iPhone editions are virtually the same phone, why doesn't the 6 also have landscape view. Both these devices should have an iPad GUI. Landscape view is the most ergonomic position. Having to switch grips from portrait to landscape increases the chance for accidental drops. Landscape also decreases the likelihood for cumulative trauma which include carpal tunnel and digititis. In short, it's just easier to navigate your phone seamlessly by keeping it in your preferred orientation. Lastly, it's sad that I'm waiting for a jailbreak. My plan is not to jailbreak. But if Apple developers can't be aware to what the mass looks for in functionality, jailbreaking may be the only answer. If you would reference Infinidock, this app allows for multiple icons to be docked. Not just four icons. Making these small additions to the user interface would vastly improve the users experience. If developers aren't willing to make such adjustments, then I suggest allowing open code for Cydia jailbreak developers that will allow for users to freely mod our devices.Believe it or not, the ability to freely mod our phones to the users preference is what separates the iPhone and Android users. Hence the jailbreak... Don't patronize your loyal consumers by making such availability this coming S model.
James Wimberley - Friday, October 3, 2014 - link
Anand team: Please consider adding ruggedness tests for mobile devices. Desktops spend their lives in sheltered environments, with a few heatwaves and power cuts and surges. Laptops are occasionally dropped. But tablets and smartphones are constantly being dropped, put in linty pockets, exposed to rain and coffee, bent, scratched, and connected to low-quality chargers. If you a ea SEAL, you need a different order of ruggedness, like the Toughbook. But normal consumer use is still quite deamnding.e34v8 - Friday, October 3, 2014 - link
I have three main complains here.The is the screen resolution. We all know 326 ppi is far, far from enough. I have always been able to see aliasing on iPhone screens (never on my Nexus 5) and aside form that, the image is just not that clear and sharp as on a good 1080p screen. Maybe the 6+ will offer great viewing experience.
The second complain is size. Yes, I think that Apple is making the right move with bigger screen size. Better late than never. The 4.7" are not the ideal size for me, but this is a major improvement. But wtf were Apple thinking, when they made a 4.7" phone, with the dimensions of a 5 or a 5.2"phone? Why? Apple customers value compactness. Just compare it with an old 4.7" phone like the Optimus G - 131.9mm vs 138.1mm .
And last, but not least - 1gb of ram. Are Apple so greedy? This is typical planned obsolescence. I still can't believe it. 64 bit SoC and a gig of ram...
The lack of OIS or wireless charging is also not good.
This phone should cost a lot less.
blackcrayon - Friday, October 3, 2014 - link
"We all know 326 ppi is far, far from enough" - Stopped reading there. It's enough for the vast majority of people, and is certainly a better idea than making a 500 ppi phone that lags.e34v8 - Saturday, October 4, 2014 - link
Well, that's your problem. You should read someone's comment, before you reply.I agree with you. I also hate phones that lag, stutter or miss frames in the UI. That is the reason I do not like Samsung and their Touch Wiz. But that's not the case with my Nexus 5. It's totally stock, but believe me, it's blazing fast and smooth. And it still manages to have a gorgeous 455 ppi screen.
Anyway, there is no such thing as a perfect phone, but Apple could have offered much more, having in mind that it's a flagship expensive device.
michael2k - Monday, October 6, 2014 - link
1) Your eyesight is superior, most aren't nearly as good as yours.2) The Optimus G is 8.45mm thick vs the 6.9mm of the iPhone 6
3) You talk about typical planned obsolescence, yet in the same breath rave about the Nexus 5. The Galaxy Nexus from 2011 won't see either the 2013 KitKat nor the 2014 Android L, whilst the 2011 iPhone 4S saw both the 2013 iOS 7 and the 2014 iOS 8. I would expect a 2014 iPhone 6 to see at least iOS 11, and still be usable! What do you think your 2013 Nexus 5 will see?
4) OIS isn't that important, especially when it already has one of the best cameras in the industry
5) This phone already sold out. Costing less is probably the last thing it needs. Ordered on Sept 20th and expect to see my phone in October 20th.
e34v8 - Thursday, October 9, 2014 - link
The fact that my eyesight is or isn't superior does not change the facts. Ignoring or denying something, without any arguments is not productive. You say that OIS is not important and that's it. Why? I can tell you, I'm never going to buy a phone without OIS again. It's much easier for me to catch perfectly focused shots and shoot steady videos.Anyway, everyone has their own view on things. I think Apple are capable of making a better phone - with thin bezels, full HD screen, more than 1 gig of ram, bigger battery... but they chose not to. I'm not some fanboy that will blindly ignore faults. The iPhone 4 was my last iPhone. I'll continue to wait for something from Apple that's worth the money.