Despite faster A8, higher pixel count of iPhone 6 Plus drives lower FPS benchmarks
With 2.1 million pixels, the Retina HD resolution of iPhone 6 Plus demands a lot more GPU performance than either iPhone 6 or iPhone 5s to render 2D and 3D graphics at its native resolution, resulting in benchmarks with--in some cases--lower frames per second rendering results in native resolution GPU tests.
The original GFXBench 3.0 GPU benchmarks AppleInsider published in our initial reviews of iPhone 6 and iPhone 6 Plus showed moderate to significant GPU improvements over iPhone 5s across the board.
However, one of the benchmark's developers, Eszter Szilva, contacted us to report that the current, public version of the app did not yet support the native resolutions of the new models' displays. Kishonti provided a prerelease GFXBench version 3.0.2 that does. The benchmark app should be released publicly soon, but the developer shared a prerelease copy so we could update our benchmark scores.
The adjusted benchmarks show that the A8 Application Processor used in iPhone 6 and iPhone 6 Plus is around 24 to 46 percent faster at low level tasks, and around 50 percent faster at higher level OpenGL ES scene rendering than the A7 chip introduced in last year's iPhone 5s, at least when rendering at the same 1080p resolution.
Apple's design of the A8 uses a four core Imagination Series 6XT GPU: reportedly the GX6450. The A7 introduced the same Series 6XT "Rogue" GPU family, but used a less capable GX6430 GPU. The A8 is also clocked slightly faster than last year's A7: 1.4 GHz versus 1.3 GHz. Both the A7 and A8 are much faster than the earlier 32-bit A6 used in the original iPhone 5 (over twice as fast).
While faster overall than the A7 iPhone 5s, the new iPhone 6 models are tasked with a more difficult job because they push significantly more pixels. While iPhone 5s has 0.7M pixels in its display, iPhone 6 has 1M and iPhone 6 Plus has over 2M.
Additionally, the 6 Plus actually renders graphics internally at an even higher 2.7M pixel resolution, then scales the results down to the physical resolution of its screen (its internal 2208x1242 rendering resolution is scaled down to fit its 1920x1080 display).
The engineering choices behind how iPhone 6 Plus draws its screen should make it easier for Apple and its third party app developers to evenly scale up existing titles or create custom, higher resolution artwork that looks great on the larger screen. It also appears to make it easier for Apple to release higher resolution iPhones in the future that use the same 2.7M pixel rendering without any scaling, so apps created today for the 6 Plus will look great automatically in the future.
The downside is that iPhone 6 Plus has to render more pixels than it actually has, and it already has nearly three times as many as last year's iPhone 5s. With so many more pixels to push, the new phone can't always beat the "frames per second" performance of iPhone 5s at its native resolution.
This means games using the newer OpenGL ES 3.0 API may render the same scene more smoothly, albeit in less detail, on both iPhone 5s or iPhone 6 than on the larger and more pixel dense display of iPhone 6 Plus (if they render their graphics at the native resolution of the new displays; most existing games currently do not).
Any existing games that don't render graphics to the devices' native resolutions but instead just present the same graphics blown up to fit the larger display of the two new models should run faster and more smoothly than they can on iPhone 5s.
Of course, the GPU benchmarks only emulate the rendering of a canned scene; in an actual video game, the graphics would be rendered alongside other calculations typically performed by the CPU, such as physics and game AI. The A8's CPU is around 20 percent faster at both integer and floating point calculations on both new models compared to the A7 used in iPhone 5s.
Apple has also noted that the newer A8 chip is far more power efficient and designed to achieve maximum performance for longer periods of sustained use than last year's A7. That should help both new models achieve better gameplay with less battery consumption, despite their higher resolutions.
Benchmark tests based on the earlier (and less sophisticated) OpenGL ES 2.0 API render slightly faster on the 6 Plus (41.5fps) than iPhone 5s (40.7fps), delivering a score with a 2 percent improvement. However, the 6 Plus was still beaten by iPhone 6 (49.9fps) given that its 4.7 inch screen has less than half of the pixels to render onscreen compared to the 5.5 inch 6 Plus. iPhone 6 turned in a score 22 percent higher than iPhone 5s.
In GFXBench's "offscreen" tests (which render the same scene at 1080p resolution regardless of the device they are run on), iPhone 6 rendered OpenGL ES 3.0 tests 43 percent faster than iPhone 5s, while the 6 Plus was 51 percent faster. In the simpler OpenGL ES 2.0 tests, both iPhone 6 and 6 Plus rendered the test scene 49 percent faster than iPhone 5s. Both also turned in alpha blending and fill scores that were 32-46 percent faster.
Apple developed Metal to specifically achieve performance gains on the A7 and A8, and the first games to make use of the new technology are just now arriving alongside the release of iOS 8. Apple is currently featuring a half dozen free and paid titles that already use Metal.
Using Metal, games and other graphics-intensive apps can fully exploit the GPU, and can also take advantage of the integrated memory architecture between the Application Processors' CPU and CPU cores. This allows Metal to coordinate the CPU's feeding of the GPU with instructions without needing to constantly pass data back and forth between a central system cache and a dedicated graphics cache.
Kishonti said it is currently working to add Metal API support to its GFX Bench tool, to enable users to see how much faster Metal-enhanced games and apps can run on their hardware compared to existing, cross platform OpenGL ES APIs.
The original GFXBench 3.0 GPU benchmarks AppleInsider published in our initial reviews of iPhone 6 and iPhone 6 Plus showed moderate to significant GPU improvements over iPhone 5s across the board.
However, one of the benchmark's developers, Eszter Szilva, contacted us to report that the current, public version of the app did not yet support the native resolutions of the new models' displays. Kishonti provided a prerelease GFXBench version 3.0.2 that does. The benchmark app should be released publicly soon, but the developer shared a prerelease copy so we could update our benchmark scores.
More horsepower, but far more pixels to push
The adjusted benchmarks show that the A8 Application Processor used in iPhone 6 and iPhone 6 Plus is around 24 to 46 percent faster at low level tasks, and around 50 percent faster at higher level OpenGL ES scene rendering than the A7 chip introduced in last year's iPhone 5s, at least when rendering at the same 1080p resolution.
Apple's design of the A8 uses a four core Imagination Series 6XT GPU: reportedly the GX6450. The A7 introduced the same Series 6XT "Rogue" GPU family, but used a less capable GX6430 GPU. The A8 is also clocked slightly faster than last year's A7: 1.4 GHz versus 1.3 GHz. Both the A7 and A8 are much faster than the earlier 32-bit A6 used in the original iPhone 5 (over twice as fast).
While faster overall than the A7 iPhone 5s, the new iPhone 6 models are tasked with a more difficult job because they push significantly more pixels. While iPhone 5s has 0.7M pixels in its display, iPhone 6 has 1M and iPhone 6 Plus has over 2M.
Additionally, the 6 Plus actually renders graphics internally at an even higher 2.7M pixel resolution, then scales the results down to the physical resolution of its screen (its internal 2208x1242 rendering resolution is scaled down to fit its 1920x1080 display).
With so many more pixels to push, the new phone can't always beat the "frames per second" performance of iPhone 5s at its native resolution
The engineering choices behind how iPhone 6 Plus draws its screen should make it easier for Apple and its third party app developers to evenly scale up existing titles or create custom, higher resolution artwork that looks great on the larger screen. It also appears to make it easier for Apple to release higher resolution iPhones in the future that use the same 2.7M pixel rendering without any scaling, so apps created today for the 6 Plus will look great automatically in the future.
The downside is that iPhone 6 Plus has to render more pixels than it actually has, and it already has nearly three times as many as last year's iPhone 5s. With so many more pixels to push, the new phone can't always beat the "frames per second" performance of iPhone 5s at its native resolution.
Adjusted native resolution benchmarks
Specifically, in "on-screen" native resolution tests using the OpenGL ES 3.0 API, iPhone 6 Plus delivered a score 22 percent lower than last year's iPhone 5s, rendering the "Manhattan" test scene at 19 fps (at its 1920x1080 display resolution; Apple's documentation clarifies that both OpenGL and Metal APIs can render directly to the resolution of the display without any intermediary scaling), compared to the 24.4fps (albeit at a much lower 1136x640 resolution) achieved by iPhone 5s. iPhone 6 rendered the same scene at 26.6 fps (at its native 1334x750 resolution), delivering a score 9 percent higher than the 5s.This means games using the newer OpenGL ES 3.0 API may render the same scene more smoothly, albeit in less detail, on both iPhone 5s or iPhone 6 than on the larger and more pixel dense display of iPhone 6 Plus (if they render their graphics at the native resolution of the new displays; most existing games currently do not).
Any existing games that don't render graphics to the devices' native resolutions but instead just present the same graphics blown up to fit the larger display of the two new models should run faster and more smoothly than they can on iPhone 5s.
Of course, the GPU benchmarks only emulate the rendering of a canned scene; in an actual video game, the graphics would be rendered alongside other calculations typically performed by the CPU, such as physics and game AI. The A8's CPU is around 20 percent faster at both integer and floating point calculations on both new models compared to the A7 used in iPhone 5s.
Apple has also noted that the newer A8 chip is far more power efficient and designed to achieve maximum performance for longer periods of sustained use than last year's A7. That should help both new models achieve better gameplay with less battery consumption, despite their higher resolutions.
Benchmark tests based on the earlier (and less sophisticated) OpenGL ES 2.0 API render slightly faster on the 6 Plus (41.5fps) than iPhone 5s (40.7fps), delivering a score with a 2 percent improvement. However, the 6 Plus was still beaten by iPhone 6 (49.9fps) given that its 4.7 inch screen has less than half of the pixels to render onscreen compared to the 5.5 inch 6 Plus. iPhone 6 turned in a score 22 percent higher than iPhone 5s.
In GFXBench's "offscreen" tests (which render the same scene at 1080p resolution regardless of the device they are run on), iPhone 6 rendered OpenGL ES 3.0 tests 43 percent faster than iPhone 5s, while the 6 Plus was 51 percent faster. In the simpler OpenGL ES 2.0 tests, both iPhone 6 and 6 Plus rendered the test scene 49 percent faster than iPhone 5s. Both also turned in alpha blending and fill scores that were 32-46 percent faster.
Pedal to the Metal
One feature GFXBench is currently unable to benchmark is how much faster games can perform when using Apple's new Metal API, announced this summer at WWDC. Using Metal, developers can bypass OpenGL ES entirely, achieving massive increases in graphics performance on the same hardware.Apple developed Metal to specifically achieve performance gains on the A7 and A8, and the first games to make use of the new technology are just now arriving alongside the release of iOS 8. Apple is currently featuring a half dozen free and paid titles that already use Metal.
Using Metal, games and other graphics-intensive apps can fully exploit the GPU, and can also take advantage of the integrated memory architecture between the Application Processors' CPU and CPU cores. This allows Metal to coordinate the CPU's feeding of the GPU with instructions without needing to constantly pass data back and forth between a central system cache and a dedicated graphics cache.
Kishonti said it is currently working to add Metal API support to its GFX Bench tool, to enable users to see how much faster Metal-enhanced games and apps can run on their hardware compared to existing, cross platform OpenGL ES APIs.
Comments
It's still art, and a pleasure to use!
And the future's so bright...I gotta wear shades.
This is hardly surprising - the iPad 3 struggles graphically compared to the iPad 2 due to its retina screen.
This is hardly surprising - the iPad 3 struggles graphically compared to the iPad 2 due to its retina screen.
Yep. And just like the iPad 3 the smart money will wait for the next models to get the revision done right. It is unfortunate but Apple has clearly made some bad decisions with the design of these new iPhones.
-kpluck
Not unexpected, and probably not a major problem for most people.
I wonder if there is a mode to run games at "half resolution" on the iPhone 6+, to drop the number of pixels that need to be rendered. It might make the games a little blurry I guess.
There's an argument that with the larger battery the 6+ contains, that the GPU in the A8 could have been run a little faster to make up for the pixel count increase.
I guess the A8X will fix this for the next iPad, and the A9 will fix it for the next iPhone.
Games will just render at a lower resolution until the speed is acceptable. This is very common in game consoles. For example, even though the Xbox 360 and PS3 both were 1080 consoles, the vast majority of games were much lower resolution. Call of Duty 4 ran at 1024x600, for example, and was scaled up to 1080.
a) I don't understand what Daniel here calls "native" resolution. Native resolution for the 6 would be 1920x1080 as this is what the screen has, and games CAN use this to render to (see the list above for speeds at 1080p, this is what we should get on the 6 ). I do think most games, once updated / developed would use exactly this scenario. It's no use to render to 1242x2208 for a game...
b) not much help for existing games, but games developed for metal would be more beneficial to show the real horsepower of the hardware.
So I think the best is to give it a bit of time until the benchmarks are changed / updated. Or middleware adapted to metal, etc. This analysis really only applies to games that are finished developed and won't be updated.
Just my $0.02
I think it's a bit too early to give much on these results.
a) I don't understand what Daniel here calls "native" resolution. Native resolution for the 6 would be 1920x1080 as this is what the screen has, and games CAN use this to render to (see the list above for speeds at 1080p, this is what we should get on the 6 ). I do think most games, once updated / developed would use exactly this scenario. It's no use to render to 1242x2208 for a game...
b) not much help for existing games, but games developed for metal would be more beneficial to show the real horsepower of the hardware.
So I think the best is to give it a bit of time until the benchmarks are changed / updated. Or middleware adapted to metal, etc. This analysis really only applies to games that are finished developed and won't be updated.
Just my $0.02
Another thing that's kinda funny is that one of the big selling point for the GPU-CPU combo was non throttling, which EVERYONE ELSE DOES. So, what is the point of having a high score in a 5 minute benchmark if you'll chug at a low frame rate after that. Like you said, lets see real game adapted to the platform played in demo mode (say 30 minute loop) and then we will know how it all foes.
The iPhone 6 Plus is just a totally lame phone anyway. This is just one more reason not to buy it. I can't wait to see people looking like idiots while they place a call with it.
Are you a midget or something?
The iPhone 6+ is definitely larger than previous iPhones, but a 5.5" phone is not that large, compared to something like an iPad.
It's also a matter of personal preference. Some people will prefer the 4.7" iPhone, while others will prefer the larger iPhone 6+.
I don't own either a 6 or a 6+, so I'm totally neutral on the size subject. Each size comes with its own advantages and disadvantages.
I can definitely see the advantages of the 6+ though. It has a better battery life, a better camera because of the optical stabilization and a larger, higher density display. I can definitely see photo interested people choosing the larger iPhone, because a bigger viewfinder is better than a smaller one. Hell, I'm one of the people who sees nothing wrong with taking pictures using an iPad, and hopefully Apple upgrades the iPad cameras also. I feel that the iPad cameras should be no worse than what is found on iPhones.
Buddy these comments will surely upset some fans.
Play nice
I don't get it. Where's the Android angle?
Is Danny Diggler ill?
Yep. And just like the iPad 3 the smart money will wait for the next models to get the revision done right. It is unfortunate but Apple has clearly made some bad decisions with the design of these new iPhones.
I would bet good money on the next iPhone plus model having a true @3x display.
Personally I'm COMPLETELY fed up with hearing all the minuses with the iPhone 6 Plus This product is a COMPLETE and abysmal FAILURE, which has Steve Jobs rolling in his grave. He'd probably ram it down Tim Cook's throat! He'd never replace how thin a product is make it less durable.
No matter what the fanboys out there say the young man on Youtube ACTUALLY bent / broke an iPhone 6 Plus with his bare hands and it hurt a LOT OF FEELINGS, when the anger should be placed at Apple for creating GARBAGE!
This makes me think of the stupid girlfriend who beats up her boyfriend's other girlfriend he's cheating with, instead of going to the source of the problem.... HIM!
Quit bashing people who find out how horrible this device is, and help Apple come to grips with it's putting out garbage, and to put them back on the right track.
You're just putting dirt into Apple's grave, and they'll become the next Microsoft.
Oh... I hurt your feelings........ get over it, and quit helping this company go in the wrong direction.
Take note: Consumer reports, and Apple NEVER showed a test where the pressure on the phone was put on the weakest part of the structure, like the button area, because it will bend, and break.
Personally I'm COMPLETELY fed up with hearing all the minuses with the iPhone 6 Plus This product is a COMPLETE and abysmal FAILURE, which has Steve Jobs rolling in his grave. He'd probably ram it down Tim Cook's throat! He'd never replace how thin a product is make it less durable.
No matter what the fanboys out there say the young man on Youtube ACTUALLY bent / broke an iPhone 6 Plus with his bare hands and it hurt a LOT OF FEELINGS, when the anger should be placed at Apple for creating GARBAGE!
This makes me think of the stupid girlfriend who beats up her boyfriend's other girlfriend he's cheating with, instead of going to the source of the problem.... HIM!
Quit bashing people who find out how horrible this device is, and help Apple come to grips with it's putting out garbage, and to put them back on the right track.
You're just putting dirt into Apple's grave, and they'll become the next Microsoft.
Oh... I hurt your feelings........ get over it, and quit helping this company go in the wrong direction.
Take note: Consumer reports, and Apple NEVER showed a test where the pressure on the phone was put on the weakest part of the structure, like the button area, because it will bend, and break.
An obvious troll like you deserves to be bashed 100%. Whoever uses "fanboy" and "Job rolls in his grave" in the same message should be forced to use a Samsung phone as torture for a whole year.
Seriously? If anything is garbage, is the dump you just put on my screen. Go make a video of you karate chopping 6+ all day long and join the circus; its all that remains for you do now after what you wrote.
Are you a midget or something?
Are you a giant or something?
The iPhone is a phone, the iPad is a tablet. People don't place call holding their iPad to their ear.
It's also a matter of personal preference. Some people will prefer the 4.7" iPhone, while others will prefer the larger iPhone 6+.
4.7 is too big already. I'll probably use an iPhone with that size already, but only because I won't have a choice.
5.5 is monstruosly gigantic. The phone looks oversized and that makes it ugly even if the design is great if you don't look at the size.
People who buy a 5.5 phone probably don't own a tablet and will never truly know what a great experience a tablet is.
I understand it can be good for some uses, but it's just not for me. I don't watch movies on my phone for instance.
I just can't wait for Apple to release a watch that can work on its own. I probably won't need an iPhone at that point.
I tried the plus in a store the other day, and this was my immediate experience too. Even just in regular use. Might get sorted out though. The iPad is not laggy, is it?
Good grief. The CPU-GPU is fast enough to render an UI screen. Get a grip. If there is lag at all (which I haven't seen), it would be in IOS 8.