domingo, 18 de novembro de 2012

Tablet Wars: Apple iPad, Microsoft Surface, Or Google Nexus 10?

The tablet market used to be very narrow only two years ago (a bit less). There was the iPad, the Motorola XOOM, the Samsung Galaxy Tab, and a few others. Now, of course, the tablet market has broadened a lot, and is starting to become just like the PC market. Most recently, Microsoft decided to jump into the tablet realm with its Surface tablet and its new ARM-compliant Windows RT, and Google decided to start making tablets too, as a part of the Nexus series, which used to include smartphones only. So now we have one representative for each of the tablet OSes, Apple's iPad 4 for iOS, Google's Nexus 10 for Android, and Microsoft's Surface for Windows RT. One question that is also necessary to determine which slate is the 'best' one is which OS is the best? Therefore, this comparison won't only compare the tablets, but will also compare the OS they run on. Let's begin with a basic specs comparison:

Apple iPad 4 Google Nexus 10 Microsoft Surface
Network Connectivity Wi-Fi + 3G/4G LTE Wi-Fi Wi-Fi
Body 241.2 x 185.7 x 9.4 mm, 652g 263.8 x 177.8 x 8.9 mm, 603g 274.6 x 172 x 9.4 mm, 680g
Display 9.7" IPS LED-backlit 2048 x 1536 Retina display (264ppi) 10.1" Super PLS TFT 2560 x 1600 (299ppi) w/Corning Gorilla Glass 10.6" TFT 1366 x 768 (148ppi)
Storage 16/32/64 GB, 1GB RAM 16/32 GB, 2GB RAM 32/64 GB, 2GB RAM
Camera (rear) 5MP (1080p video) w/LED flash, autofocus, face detection 5MP (1080p video) w/autofocus, face detection, video stabilization 1.2MP (720p video)
Camera (front) 1.2MP (720p video) w/face detection 1.9MP 1.2MP (720p video)
OS iOS 6 Android 4.2 Jelly Bean Windows RT
Chipset/CPU Apple A6X (Dual-core Swift @ 1.4GHz + quad-channel LPDDR2-1066 memory) Samsung Exynos 5250 (Dual Cortex-A15 @ 1.7GHz + dual-channel DDR3-1600 memory) NVIDIA Tegra 3 T30 (Quad Cortex-A9 @ 1.3GHz + single-channel LPDDR2-1066 memory)
GPU PowerVR SGX554MP4 Mali-T604 NVIDIA 12-core GeForce

Design









































These three tablets have unique designs, and are all a pleasure to look at, each with its pros and cons. Statistically speaking, however, I believe that the best design title goes to the Nexus 10, since it is the thinnest one, as well as the lightest (see specs). The iPad may not be as light, or as thin, but it still feels and looks good. The same can't be said about the Microsoft Surface, however. The Surface is as thick as the iPad 4, however, it is, simply put, a brick. At 680g, it is as heavy (or even heavier) than some of the first-gen tablets (the ASUS Eee Pad Transformer, for instance, weighed 680g too, and so did the first-gen iPad). The Surface's weight is simply unnacceptable for this time. That aside, the design of these slates can't be classified as better or worse; it is something each user defines. Each of these designs have their unique features, some people will like them, others won't.

Display

The interesting thing here is that we have three slates, all with different aspect ratios. Depending on the use, each of these aspect ratios may be the better one (or not). Let's begin with what I consider to be the worst display of these three tablets.
The Microsoft Surface uses a 1366 x 768 display, which corresponds to a 16:9 aspect ratio. At an unusual screen size of 10.6", this translates into a 148ppi pixel density. The pixel density is on par with last-gen Android and Apple slates, but is about half of what these other two tablets offer, as a result, the screen isn't very crisp, images are not clear, and text is not sharp. The screen's color is not exactly the best, but it's not really bad. Also, the 10.6" screen might be a little too large for some people (me included). The 16:9 aspect ratio is excellent for viewing widescreen movies, however, it makes the display a tad too wide. It makes the tablet look strange.
Next is the Apple iPad 4's display, the legendary and slightly overrated Retina Display. Apple was the first to choose an incredibly large display of 2048 x 1536 resolution, which resulted in a stunning 264ppi pixel density. As a result, text is razor sharp, and images are bright and clear. Apple continues delivering, also, some excellent color reproduction on the iPad 4; colors are bright and vivid, unlike most other tablets. The 4:3 aspect ratio makes the iPad almost square, and the aspect ratio might cause movies to be displayed with those annoying black bars, however, 4:3 is very good for web browsing.
Finally, we have the Nexus 10's impressive display. This tablet breaks the record of tablet screen resolution the iPad set and delivers a stunning 2560 x 1600 display, which, at the 10.1" size, gives an aggressive 299ppi pixel density, making the term 'Retina Display' lose some of its luster. The Nexus 10 has Samsung's PLS display, which has been used in many of the company's Galaxy Tab slates. At any rate, PLS has proved to deliver very vivid colors, boasting some excellent color reproduction. The Nexus 10 was reported to have rather poor contrast ratio, as well as brightness, but it still delivers excellent visuals, but it shouldn't perform very well outdoors in bright, sunny days. The 16:10 aspect ratio is similar to the one in the Microsoft Surface, but it doesn't have the issue of being so wide it looks weird. Simply put, the 16:10 aspect ratio is the balance between being too square and too wide.

Performance

I can't include benchmarks of the Microsoft Surface here, because Windows RT still doesn't have any synthetic benchmarks available, however, I will be including benchmarks of the same SoC (Tegra 3 T30), but on an Android device (The ASUS Transformer Prime). The Surface uses an NVIDIA Tegra 3 SoC (T30 variant), which has a Quad-core Cortex-A9 CPU @ 1.3GHz, and NVIDIA's own 12-core GeForce GPU, with a quite shabby single-channel LPDDR2-1066 memory interface (although other Tegra 3 iterations use better DDR3L memory). Microsoft's choice of using the Tegra 3 was very weird to me, considering that NVIDIA's SoC is an aging, one-year-old chip. The story is different with Apple's and Google's slates, which are both debuting a brand new SoC. The iPad 4 debuts the Apple A6X chip, which has a dual-core Swift CPU @ 1.4GHz. Swift is a custom CPU architecture created by Apple. The A6X also includes a PowerVR SGX554MP4 GPU, together with the same crazily wide memory controller found in the A5X (four LPDDR2-1066 channels), resulting in 12.8GB/s theoretical memory bandwidth.
The Nexus 10 debuts the Samsung Exynos 5250 SoC, which is the first SoC to use ARM's Cortex-A15 CPU architecture. The SoC has a two Cortex-A15 cores ticking at 1.7GHz. The GPU in the Exynos 5250 is the brand new Mali-T604 GPU, which is also the first GPU to use the new midgard architecture, including an unified shader architecture. The memory interface, much like the A5X/6X, can achieve 12.8GB/s theoretical bandwidth, but in a different approach (two DDR3-1600 channels).
Now let's see what synthetic benchmarks tell us about these SoCs.


Geekbench tests mainly the compute power of the CPU. The NVIDIA Tegra 3's age shows here. After all, in its time, it was the absolute champion of CPU benchmarks, although now it isn't very good. For a brand new CPU, the Apple A6X's dual-core Swift doesn't impress, either. It is only a bit more powerful than the one-year-old Tegra 3. On the Nexus 10, we enter another realm, however. We see that the dual Cortex-A15 inside the Exynos 5250 really blasts all other competition out of the water, setting a new benchmark for mobile CPU compute power.


We can see just how poorly the Tegra 3 performs in terms of fill rate. We can say that the SoC's age is partially to blame here, but to be honest fill rate was never the Tegra 3's strong point. We also se a 50%+ gap between the Nexus 10 and the iPad 4. This is very strange, because both SoCs have equal theoretical memory bandwidth figures (12.8GB/s), but in any case, we see Apple is really ahead in terms of fill rate. Fill rate has always been a real forte for iDevices, after all. The Exynos 5250 isn't shabby at all, however, seeing as it is miles ahead of the other Android-based competition.



The Egypt HD test is the test that will relate closest to real gaming experience. Both the offscreen and onscreen test tell pretty much the same thing: that the Tegra 3 is an aged, last-gen GPU that cannot compete with today's competition, and therefore means that the Surface is not exactly good for gaming enthusiasts. We can also see, once again, the significant margin between the PowerVR SGX554MP4 in the A6X and the Mali-T604 in the Exynos 5250, but, then again, it is apparent that the Nexus 10 is far ahead from the Android competition (except in the Onscreen test, where the Nexus 10's immense resolution restrains it).

 


Once again, the A6X shows unprecedented performance in triangle throughput. In terms of our other two competitors, we get a unusual little surprise here. The Nexus 10 shows some very poor triangle throughput. Well, anyone who has seen ARM's last GPU benchmarked, the Mali-400MP, will know that ARM isn't very good on their geometry processing. The Mali-400 is known for having some of the lowest geometry processing power recently seen on a GPU. While ARM's new midgard architecture did help the new Mali-T6xx GPUs' geometry processing, and there is a very large improvement over its predecessor, it still isn't up to scratch. It scores even lower than the old Tegra 3. Although, it can be said that triangle throughput is something of a forte for NVIDIA, and that reflects on the fact that despite the Tegra 3's age, it can still compete fairly well with newer GPU competition. Still, the good triangle throughput doesn't save the Tegra 3 from being considered a weak GPU.

It is obvious from these tests that the Nexus 10 can take the crown for CPU power, and also packs a punch in terms of gaming performance and fill rate. The iPad 4, as usual, doesn't really excel on CPU capability, but it retrieves Apple's usual lead on the GPU performance. The same can't be said for the Microsoft Surface, however. Microsoft chose an aged SoC which, despite having been very powerful in its time, can no longer compete with the competition. It was inevitable that performance would be low. The CPU is still up to scratch, and isn't that far behind, however, the memory bandwidth (which hasn't ever really been very good) sets the Surface back, and the GPU performance is just awful, which means that the Surface isn't really a powerhouse for gaming.

OS: No such thing as a winner here!

I have spent countless hours comparing iPad iterations to different Android tablets, and I can't help but reflecting upon the numerous times when I've seen this question arise: Which OS is better, iOS or Android? This question still persists, only now it also includes Windows RT. The plainest answer to this question is: there is no true better OS; it really depends upon each person's needs. Since I can't directly put these three OSes into competition, I shall talk about them individually.

iOS

iOS reflects the user-friendliness and simplicity that Apple was always known for delivering. You can understand how it works almost immediately. The apps are organized on a grid, with a lot of space between each icon (on the iPad the grid is 5x4). There is not much customization on the iOS UI, you can only change the wallpaper. The simplicity of the UI makes it extremely easy to learn, and therefore very user-friendly. Also, iOS, due to its simplicity, has always been very fast and fluid, so you shouldn't perceive any type of lag anywhere. iOS is also very fun to use, incorporating a variety of multi-touch gestures for operations like multi-tasking. To wrap it up, iOS has the widest variety of apps on the mobile OS space, and also has, by far, the largest amount of tablet-optimized apps. Basically, iOS is the most mature mobile OS we have.

Android
Android, which is Google's concept of a mobile OS, can still be considered a not-so-mature OS. It is still undergoing vast developments, but each new Android iteration is a vast step forward. The Nexus 10 comes with the latest Android 4.2 out of the box. Android is known for, unlike iOS, being more complicated to understand and use, however, it has plenty of customization. Apart from the normal app icons, you can add widgets to the home screen, which give you quick and easy access to things like weather, e-mail, etc., but Android surely doesn't look as clean and simple as iOS. Android used to be a slow and laggy OS, but Google's recent Project Butter has siphoned out most of the laggy bits. Of course, Android still isn't perfect, you can still perceive some slight lags and slowdowns here and there, but it's nothing of a big deal. Android also has many apps available, however, few of them are really optimized for tablets (the situation is getting better, though).

Windows RT

Oh, the brand new Windows RT. It is only a few weeks old, so it is still in its early stages. This means that there aren't many apps for the OS, but that should start to change soon enough. For a brand new OS, Windows RT is very solid, and looks very mature. It is also the mobile OS that looks the most different. iOS and Android use things like app icons and (Android only) widgets. Windows RT combines both on a concept called 'Tiles'. The Tiles are arranged very close together, and they update in real time, so they are very useful for displaying weather, e-mail, news, and stuff like that in a single page. Like iOS, Windows RT uses a variety of gestures for basic commands like switching and closing apps, and Windows RT is excellent for multi-tasking, being the first mobile OS to support displaying two apps at the same time. Windows RT also has a desktop mode, which uses a UI that is much similar to the traditional Windows UI. Windows RT is very fast, fluid, and it looks great. It is a new OS in its early stages, however, it is an extremely promising one.

Conclusion

Well, now I face the most difficult decision I have to take in this article, which is, answering which of these tablets is the best one. No doubt, they all have their strong points and weak points, which will make them more adequate for some people and less adequate for others, therefore, it isn't easy to tell which is definitely better. The Microsoft Surface RT, as we have seen, doesn't offer excellent specs at all. Its display is really no big deal, the camera is ridiculously weak, and the tablet will suffer with performance because it uses an aged, weak SoC. It is also unusually heavy, and not as thin as its other specs should suggest. But what makes the Surface RT a good tablet? well, it's built-in kickstand might be alluring to some, and it has the luxury of having the revolutionary touch cover, which, like the iPad's smart cover, protects the screen, and then opens to reveal an extremely thin, light keyboard. Also, the Surface RT has what I believe to be the most promising mobile OS, incorporating a great UI with great performance and excellent functionality. Basically, the Surface is the perfect work companion, having the luxury of being the first mobile device to have Microsoft Office installed. The Google Nexus 10, the biggest step in Android tablets ever seen, is the perfect tablet for those who care about visuals and ergonomics. The device is remarkably thin, light, and has by far the crispest screen ever seen on a tablet, delivering bright images and sharp text, while handling it all with some very reasonable performance. So the Nexus 10 goes to people who are allured by an outstanding display. Apple's iPad 4 is perfect for performance enthusiasts. It packs a real punch in its SoC which not only handles easily its also large Retina Display, but can also show outstanding performance with it. The iPad also offers a marvel of content, with literally an app for everything. Apart from that, there's the solidness that Apple has always offered in its iDevices; the almost crash-free UI, the user-friendliness.
That is the advantage of having a variety of competitors in a market: at this point, for every type of person and preference, there is an ideal tablet PC.


sexta-feira, 16 de novembro de 2012

Nexus 10's SoC, Samsung Exynos 5250 review


Google's new Nexus 10 tablet, which was developed alongside Samsung, features some killer specs, most notably, the unsurpassed screen resolution of 2560 x 1600 pixels. This immense resolution results in a fine 299ppi pixel density, surpassing even the iPad's 264ppi display. However, performance demand is proportional to resolution, therefore, to be able to power such a powerful display, Google needed an extremely powerful SoC, something of the likes of Apple's A5X SoC. Well, Google has done right in choosing Samsung's brand new Exynos 5250 SoC. The Exynos 5250 is built on Samsung's successful 32nm HKMG (High-K Metal Gate) process. 

The CPU

Less than a year ago, all SoC manufacturers were bound to Cortex-A9 CPUs, so there was no real competition in terms of single-threaded performance, since it was all the same. Today, of course, the story is different. ARM's Cortex-A15 architecture leveraged certain ARM-based CPU designing companies into making similar architectures. Currently, we have three new architectures competing with each other, Qualcomm's Krait, Apple's Swift, and ARM's Cortex-A15. The real difference between these is single-threaded performance. While the Swift didn't really surprise anyone, and Krait, well, did a pretty good job, the Cortex-A15 is just astounding on a per-core basis. Indeed, one A15 core is about twice as fast as one Krait core. Now, The Exynos 5250 has two A15 cores clocked at 1.7GHz, which theoretically should translate into the best mobile CPU performance ever seen.

Now let's see how two A15s @ 1.7GHz fare against the Quad-core Krait @ 1.5GHz and the dual-core Swift @ 1.4GHz.


The Exynos 5250 in the Nexus 10 distinguishes itself clearly from the rest of the competition, and it does that, while also being one of the few who have only two cores (granted, it has the highest clock). Comparing it to the only other dual-core processor there, the Swift, found in the Apple A6X flagship SoC, we can see that per-core efficiency is unprecedented in the Cortex-A15.

Memory interface

The main constraint that a high-resolution screen poses is memory bandwidth. Considering how bad Android devices' SoCs usually do in terms of memory bandwidth, the Exynos 5250 was a true surprise. This SoC contains a dual-channel DDR3-1600 (800MHz) memory controller, bringing the theoretical memory bandwidth to a PC-class 12.8GB/s. Apple's A5X and A6X chips (both powering an iPad's Retina display) both achieve the same bandwidth as the Exynos 5250, theoretically speaking, only with a much wider memory interface (quad-channel LPDDR2-1066). That said, the Exynos 5250 is the first non-Apple SoC ever to be able to power such a fine display as the Nexus 10's.

The GPU

Another big surprise that comes with the Exynos 5250 is the brand new Mali-T604 GPU, built by ARM. It is the first GPU to use ARM's new midgard architecture, which is a new unified shader architecture. As we will see in the benchmarks below, the Mali-T604 kills the GPU inside the A5X, but lags behind the A6X. At any rate, it is by far the best GPU on the Android space.


Despite the theoretical memory bandwidth of the Exynos 5250 being equal to Apple's A6X, we clearly see that there is a huge gap between the A6X's maximum fill rate and the Exynos' maximum fill rate. Aside from the A6X, the Exynos 5250 shows excellent fill rate, leaving the other competition in the dust, and it should surely be able to handle properly the Nexus 10's immense display resolution.



Unfortunately, we see in the Offscreen Egypt HD test that the iPad 4's PowerVR SGX554MP4 GPU is actually significantly stronger than the Mali-T604, which only edges ahead of the Adreno 320. Still, it performs very well, and is the most powerful GPU on the Android space. The Onscreen test shows us the sad reality that the 2560 x 1600 display is a bit too demanding for the Mali-T604. The overall weaker GPU, combined with the significantly higher reolution, resulted in the Nexus 10 performing much worse than the iPad 4. Despite that, and taking into consideration the unprecedented resolution, the Mali-T604 does offer some reasonably good performance, and should suffice for most gaming uses.



Here is the part where Mali GPUs always get disappointing. ARM's GPUs have never been very good at their triangle throughput. We can see that the T604's midgard architecture has really improved Mali's triangle throughput, looking at the improvement since the last-gen Mali-400MP, but it is still humiliating for ARM. The triangle throughput isn't even comparable to what the iPad 4 offers, and even the 1-year-old NVIDIA Tegra 3 edges ahead (granted, triangle throughput is NVIDIA's forte). It should be good enough to power most games, but in situations where the polygon count is very high, the weak triangle throughput could act as a performance bottleneck.

Conclusion

We've seen that the Samsung Exynos 5250 has its strong points, but we've also seen a weak side to Samsung's new flagship SoC, although the vast majority of the SoC's features are excellent. The Exynos 5250 is a very interesting SoC because it uses new architectures for almost everything; it is the first to use ARM's Cortex-A15 CPU design, and also the first to have ARM's new Mali-T604 GPU. As a result, the midgard architecture also debuts with the Exynos 5250. Unlike most of the current SoCs, the Exynos 5250's features are all fine, from the die process to the CPU, the GPU and the memory controller. We also get the best from power efficiency, thanks to Samsung's 32nm HKMG process and the Cortex-A15, which proved to be quite an efficient CPU. The Nexus 10 is a very demanding device, and the Exynos 5250 is the only SoC capable of satisfying the new slate's needy demands.

segunda-feira, 5 de novembro de 2012

ASUS VivoTab RT review

ASUS has proved to be an excellent tablet maker with its Transformer series of Android tablets and its Google Nexus 7 tablet. The enhanced productivity that the Transformer Pad keyboard dock offered was very alluring, and has been a good selling point for ASUS. Now with the new promises that Microsoft's new Windows RT platform offer, ASUS took the lead in being Microsoft's first launch partner for the Windows RT platform, releasing the VivoTab RT alongside Microsoft's own Surface tablet. The VivoTab RT takes everything people love about ASUS tablets (thin, and light design, fast performance, etc) and puts it into the Windows RT platform.

ASUS VivoTab RT Apple iPad 4 Google Nexus 10
Body 8.3mm thick, 525g 9.4mm thick, 652g 8.9mm thick, 603g
Display Super-IPS+ 10.1" LED-backlit (1366 x 768) w/ Corning Fit Glass and ASUS TruVivid IPS LED-backlit 9.7" Retina Display (2048 x 1536) Super PLS TFT 10.1" (2560 x 1600) w/ Corning Gorilla Glass
Storage 32/64 GB + 2GB RAM 16/32/64 GB + 2GB RAM 16/32 GB + 2GB RAM
Camera (rear) 8MP w/LED flash, autofocus, geo-tagging, 1080p video 5MP w/ autofocus, face detection, 1080p video w/ video stabilization 5MP w/autofocus, LED flash, face detection, 1080p video
Camera (front) 2MP 1.2MP 1.9MP
OS Windows RT iOS 6 Android 4.2 Jelly Bean
Chipset NVIDIA Tegra 3 T30 (Quad Cortex-A9 @ 1.3GHz + 12-core GeForce @ 520MHz + single-channel DDR3L-1500 memory) Apple A6X (Dual-core Apple Swift @ 1.4GHz + PowerVR SGX554MP4 quad-core GPU + quad-channel LPDDR2-1066 memory) Samsung Exynos 5250 (Dual Cortex-A15 @ 1.7GHz + Mali-T604 GPU + Dual-channel DDR3-1600 memory

Design




Who can deny it? ASUS has a knack for well-finished metallic designs. We've seen this with the Transformer Pad Prime and Infinity. The VivoTab RT has a simplistic, yet amazing metallic back cover. Another thing ASUS is known for is having the thinnest and lightest tablets in the market. The VivoTab RT, together with the Transformer Pad Prime, are the thinnest 10-inchers ever seen, measuring a svelte 8.3mm thickness. Also, the VivoTab RT sets a new benchmark for tablet weight. Weighing an astounding 525g, the VivoTab RT is by far the lightest 10-incher ever. You may like it or not, but ASUS definitely has a unique skill for design.

Display

Sure, the VivoTab RT has a substandard resolution for a tablet. Its pixel density doesn't compare to the iPad's Retina Display and the Google Nexus 10's 2560 x 1600 display, so text isn't as sharp, and pictures are not as clear. Don't be so quick to judge the VivoTab RT's display as horrible, though, because colors are vivid, thanks to ASUS' TruVivid technology, and the Super IPS+ technology (a speciality of ASUS' tablets) boosts brightness to a whopping 700nits, making the display, to some extent, outdoor readable. If you care a lot about the display, keep in mind that the VivoTab RT's screen isn't very good.

Performance

The VivoTab RT, just like the Microsoft Surface and most other tablets, uses the NVIDIA Tegra 3 chipset. Specifically the two Windows RT slates use the T30, which is the mid-range Tegra 3. CPU performance is excellent, and graphics and memory performance is average, but in any case the Tegra 3 is well-prepared to take on the Windows RT's UI smoothly. I personally think that the choice of using the Tegra 3 was foolish for both Microsoft and ASUS, since that SoC is practically aged and its momentum has already faded. It would've been a much smarter choice to use a Qualcomm Snapdragon S4 Pro quad-core SoC, which is one of the fastest. The Tegra 3 just can't compete with what Google and Apple are offering on their latest slates.

Conclusion

The VivoTab RT is currently the best Windows RT tablet (yes, in overall it is better than the Surface), however, both this slate and the Windows RT platform itself are quite premature. This, of course, is expected, since Windows RT is a brand new and fresh platform. Currently there are very few apps on the Windows Store, but given the success that this platform is promising, developers should start giving Windows RT attention. For now, Windows RT is a bad platform, but that's something that I'm confident will change eventually. The VivoTab RT doesn't have the best display, nor the best performance, but I believe that it certainly has the ability to compete with Apple and Google's offerings. 

sexta-feira, 2 de novembro de 2012

Apple A6X SoC Analyzed: Dual-core Swift and quad-core PowerVR SGX 554MP4


So we have the iPad 4 coming out today, and Apple previously made a claim that the SoC (System-on-Chip) powering it would be twice as fast as the previous generation iPad's A5X SoC. Well, we just got some benchmark results on the iPad 4, and they only seem to prove that indeed, the A6X is at least twice as good as the A5X, and in some benchmarks even more than twice.

CPU first, of course. The A6X features a dual-core CPU based on a custom architecture made by Apple, named Swift, much like in the iPhone 5, except the A6X's CPU is clocked at 1.4GHz, as opposed to 1.3GHz in the A6. The performance of the A6X CPU is ok, and is able to keep up with what the Android competition currently offers, not more, not less.


CPU performance has never been Apple's focus, but in the iPad 4 it's ok, at most. At the very least, it matches (and slightly outperforms) the Galaxy S III, at the same clock speed but with two cores less, but it is still destroyed by Samsung's Exynos 5 Dual, Qualcomm's Snapdragon S4 quad-core, and to some extent NVIDIA's Tegra 3. On a per-core performance perspective, Apple's Swift is very good, although the per-core king of the hill now is the new Exynos 5250.

Before going into the GPU, I'll quickly talk about the memory interface in the A6X. Like in the A5X, the memory interface in the A6X is the widest one ever seen on a mobile device. The A6X features a quad-channel LPDDR2-1066 memory controller, bringing the theoretical memory bandwidth up to an impressive 12.8 GB/s. This is, of course, necessary to power the 2048 x 1536 display in the iPad 4.

And then there's the GPU, the biggest change in the A6X. Apple has always been known for pushing the mobile graphics performance forward, and it has done just that again. The A6X features a stunning PowerVR SGX554MP4 quad-core GPU. The main difference between the 543 used in previous-gen iPads and the 554 is a doubling in ALU count per core. having four cores, this, therefore, means that the 554MP4 has a total of 32 ALUs, as opposed to 16 ALUs in the 543MP4, therefore, at the same clock speed, we get doubled performance since the A5X. If we assume that the clock speed remains unchanged, this results in a revolutionary 64 GFLOPS of peak theoretical performance. Apart from that, we get the same PowerVR goodness Apple has always benefited from; a TBDR (Tile Based Deffered Renderer) with unified shader architecture.




The Offscreen Egypt HD test shows us that the SGX 554MP4 is much more powerful than the Adreno 320, but in the Onscreen test, what puts the iPad 4 behind the Adreno 320-boasting PadFone 2 is the iPad 4's immense resolution.



As we can see, the iPad 4 is at the top in every benchmark, except for the Egypt HD Onscreen test, where the iPad's large resolution limits its performance, but at any rate, the margin between the PadFone 2 and the iPad 4 in the onscreen test is almost insignificant. We can see that, once again, Apple has managed to put itself at the very top of mobile graphics performance, by a very large margin.


All of that power results in a giant die area of 123mm2. It is really very large, considering that it is build with Samsung's 32nm HKMG (High-K Metal Gate) process. The A6X sets a new benchmark for other competitors to reach. Samsung's Exynos 5250, despite being from the same generation as the A6X, has already lost to it. The warning goes to NVIDIA, mainly. The graphics company's upcoming Tegra 4 'Wayne' SoC is rumored to have a quad-core Cortex-A15 CPU (which is double the performance of the already champion Exynos 5250), and a Kepler based GPU that allegedly has 24 cores, and will be built on 28nm process. We can rest assured that a quad-core Cortex-A15 will be more than enough, and 28nm will also bring the Tegra series up to date. A Kepler GPU seems promising, too, but NVIDIA will have to work hard if it wants to beat the new graphics performance (and also memory bandwidth) king of the hill, the Apple A6X.