iPad's Apple A4 CPU is feature-stripped ARM Cortex-A8 - report
Though early reports and speculation suggested Apple's custom A4 system-on-a-chip found inside the iPad was based on the more advanced, dual-core ARM Cortex-A9 architecture, one new report says the processor actually "just isn't anything to write home about."
Citing anonymous sources, Jon Stokes of Ars Technica wrote Sunday that the A4 is a custom 1GHz system on a chip with a single Cortex-A8 CPU and a PowerVR SGX GPU. Apple has not revealed specifics on the design of its processor aside from its speed, but has touted that the A4 was designed in-house by the company for the forthcoming iPad.
"In all, the A4 is quite comparable to the other Cortex A8-based SoCs that are coming onto the market, except that the A4 has even less hardware," the report said. "The iPad doesn't have much in the way of I/O, so the A4 itself can do away with the I/O that it doesn't need. In contrast, the typical Cortex A8-based SoC has more I/O hardware than a mobile phone can use, because you never know what customers will need which interface types."
The Cortex-A8 allegedly found in the iPad is the same chip that has been in the iPhone 3GS since it debuted last June. The major difference: The iPhone 3GS chip is clocked at 600MHz, while the Apple A4 is allegedly 1GHz.
So why bother with custom silicon? By forgoing some features commonly found on other Cortex-A8 devices, Apple can likely squeeze more power out of the processor than others, Stokes said. For example, the iPad "may well be the only" Cortex-A8-based device that does not have a built-in camera, "so Apple has probably ditched some dedicated image processing blocks."
"With one 30-pin connector on the bottom and no integrated camera of any kind, the A4 needs a lot less in the way of I/O support than comparable chips that are intended for smartphones or smartbooks," he wrote. "This means that the A4 is just a GPU, a CPU, memory interface block (NAND and DDR), possibly security hardware, system hardware, and a few I/O controllers. It's lean and mean to a degree that isn't possible with an off-the-shelf SoC."
He also went on to say that it's not clear whether P.A. Semi, the fabless chip designer Apple bought in 2008 for $278 million, had a part in the design of the A4. He said if the acquisition did play a part, the most likely area would be dynamic power optimization.
"It's entirely possible that the majority of the P.A. Semi team's efforts are going not into an iPad chip, but into an SoC for the iPhone," he wrote. "Because the iPad's LCD is so large and its power draw so great relative to the other components, it's hard to imagine that the A4 gives the iPad more than a few percent battery life advantage vs. a chip like the Snapdragon -- in the grand scheme of things for a tablet device, the extra hardware that chips like the Snapdragon and the i.MX515 have on A4 probably doesn't matter a whole lot."
If true, the Ars Technica report soundly refutes a previous claim that the iPad included an ARM Cortex-A9-based CPU. Bright Side of News also incorrectly reported that the iPad had an ARM Mali 50-series GPU.
Regardless of the technology found in the A4, Apple is predicted to have spent about $1 billion to design its own custom silicon. And as noted in AppleInsider's hands-on impressions with the iPad, the processor makes even Apple's speedy iPhone 3GS seem a little slow.
Apple, which has been a licensee of the ARM architecture for years, claims the power efficiency of the chip will allow the iPad to offer users 10 hours of battery life in use, and over a month of standby.
"iPad is powered by our own custom silicon. We have an incredible group that does custom silicon at Apple," company co-founder Steve Jobs said during the company's iPad keynote. "We have a chip called A4, which is our most advanced chip we've ever done that powers the iPad. It's got the processor, the graphics, the I/O, the memory controller -- everything in this one chip, and it screams."
Citing anonymous sources, Jon Stokes of Ars Technica wrote Sunday that the A4 is a custom 1GHz system on a chip with a single Cortex-A8 CPU and a PowerVR SGX GPU. Apple has not revealed specifics on the design of its processor aside from its speed, but has touted that the A4 was designed in-house by the company for the forthcoming iPad.
"In all, the A4 is quite comparable to the other Cortex A8-based SoCs that are coming onto the market, except that the A4 has even less hardware," the report said. "The iPad doesn't have much in the way of I/O, so the A4 itself can do away with the I/O that it doesn't need. In contrast, the typical Cortex A8-based SoC has more I/O hardware than a mobile phone can use, because you never know what customers will need which interface types."
The Cortex-A8 allegedly found in the iPad is the same chip that has been in the iPhone 3GS since it debuted last June. The major difference: The iPhone 3GS chip is clocked at 600MHz, while the Apple A4 is allegedly 1GHz.
So why bother with custom silicon? By forgoing some features commonly found on other Cortex-A8 devices, Apple can likely squeeze more power out of the processor than others, Stokes said. For example, the iPad "may well be the only" Cortex-A8-based device that does not have a built-in camera, "so Apple has probably ditched some dedicated image processing blocks."
"With one 30-pin connector on the bottom and no integrated camera of any kind, the A4 needs a lot less in the way of I/O support than comparable chips that are intended for smartphones or smartbooks," he wrote. "This means that the A4 is just a GPU, a CPU, memory interface block (NAND and DDR), possibly security hardware, system hardware, and a few I/O controllers. It's lean and mean to a degree that isn't possible with an off-the-shelf SoC."
He also went on to say that it's not clear whether P.A. Semi, the fabless chip designer Apple bought in 2008 for $278 million, had a part in the design of the A4. He said if the acquisition did play a part, the most likely area would be dynamic power optimization.
"It's entirely possible that the majority of the P.A. Semi team's efforts are going not into an iPad chip, but into an SoC for the iPhone," he wrote. "Because the iPad's LCD is so large and its power draw so great relative to the other components, it's hard to imagine that the A4 gives the iPad more than a few percent battery life advantage vs. a chip like the Snapdragon -- in the grand scheme of things for a tablet device, the extra hardware that chips like the Snapdragon and the i.MX515 have on A4 probably doesn't matter a whole lot."
If true, the Ars Technica report soundly refutes a previous claim that the iPad included an ARM Cortex-A9-based CPU. Bright Side of News also incorrectly reported that the iPad had an ARM Mali 50-series GPU.
Regardless of the technology found in the A4, Apple is predicted to have spent about $1 billion to design its own custom silicon. And as noted in AppleInsider's hands-on impressions with the iPad, the processor makes even Apple's speedy iPhone 3GS seem a little slow.
Apple, which has been a licensee of the ARM architecture for years, claims the power efficiency of the chip will allow the iPad to offer users 10 hours of battery life in use, and over a month of standby.
"iPad is powered by our own custom silicon. We have an incredible group that does custom silicon at Apple," company co-founder Steve Jobs said during the company's iPad keynote. "We have a chip called A4, which is our most advanced chip we've ever done that powers the iPad. It's got the processor, the graphics, the I/O, the memory controller -- everything in this one chip, and it screams."
Comments
Apple has not revealed specifics on the design of its processor aside from its speed, but has touted that the A4 was designed in-house by the company for the forthcoming iPad.
I'm willing to bet there is some sort of EFI reading SSD, phoning home like DRM scheme embedded into the processor too.
The iPad is to be a content delivering device, but what's scary is the fact that Apple has removed all but one MacBook for a line of iPad media devices.
Doesn't sound too good for the future of traditional computers.
And what's with the Apple propaganda plug at the end of the article?
I'm willing to bet there is some sort of EFI reading SSD, phoning home like DRM scheme embedded into the processor too.
The iPad is to be a content delivering device, but what's scary is the fact that Apple has removed all but one MacBook for a line of iPad media devices.
Doesn't sound too good for the future of traditional computers.
And what's with the Apple propaganda paragraph at the end of the AI article? :P
WTF are you blathering about???
There is the plastic Macbook and the whole line of Pro's (the 13" pro replaced the higher end black macbook). If anything, there are more Macbook models now than before.
If anything, there are more Macbook models now than before.
Not, do your homework. One MacBook only.
Not, do your homework. One MacBook only.
MacBook / MacBook Pro - semantics!
I think the Wii analogy is perfect. Geeks refuse to buy it because they think the hardware is obsolete. The rest of the world buys it because it's fun.
The Great iPad/iPod/iPhone Fragmentation continues . . . .
Only in your mind.
Its doing fine in the real world.
If true, I hope the A4 does not make it into the next iPhone. With the iPad potentially running a year old processor, I guess the prospects of multitasking in OS 4.0 is looking pretty dim.
I'd love to see you try to explain why Apple's A4 chip, of which you have no knowledge, is capable/incapable of driving Apple's next take on multi-tasking in 4.0? (of which you also have no knowledge)
Current jailbroken iPhones can use Backgrounder, a feature that enables per-diem multi-tasking, with almost no impact on performance. Only battery life, which is a no-brainer/to-be-expected.
The 3GS has enough horsepower and RAM to run two apps at once with no noticeable drop in performance.
So where is the validity that a better and faster chip wouldn't be capable of what the current much slower chip already is?
I'm willing to bet there is some sort of EFI reading SSD, phoning home like DRM scheme embedded into the processor too.
Name the Apple computers/devices that phone home today.
The iPad is to be a content delivering device, but what's scary is the fact that Apple has removed all but one MacBook for a line of iPad media devices.
Doesn't sound too good for the future of traditional computers.
Apple changed the top end of the MacBook line into MacBook Pros and priced them just the same as the previous top-end MacBooks. If that's "removal", then I'm all for it.
If true, I hope the A4 does not make it into the next iPhone. With the iPad potentially running a year old processor, I guess the prospects of multitasking in OS 4.0 is looking pretty dim.
If true, the A4 is running at least 67% faster than the CPU in the 3GS. Why wouldn't that make any difference?
Techno-geeks focus on the inputs, the rest of the world focuses on the outputs. By making the A4 a mysterious black box, Apple avoids all of the noise from geekdom and focuses people's attention on the overall product.
I think the Wii analogy is perfect. Geeks refuse to buy it because they think the hardware is obsolete. The rest of the world buys it because it's fun.
Very good analogy. However, the Wii is becoming obsolete because it is the same SKU that's been on shelves since 2006. It's unique and appeals to certain Family/Old Folks demographic, but even a good product can't stand up to a world of fast moving, frequently updated technology.
5 years ago most people did not have HDTVs. Now, Most Do. Huge difference. The XBox 360 with HD output started out as very very niche, now it is standard.
I think its safe to say that the average 2010 uninformed consumer who has an HDTV and picks up a Wii will be somewhat disappointed when they see the analog resolution.
Nintendo just needs to quietly refresh the hardware with HDMI output. That's all, they don't really need to change a thing.
MacBook / MacBook Pro - semantics!
Thanks
My point exactly.
Apple introduces a line of iPads, but it's not ready for market yet. As soon as sales pick up all Apple has to do is eliminate the one remaining white MacBook model as it already phased out the other MacBook models.
The iPad is intended to replace Apple's traditional computers in the younger market.
Why is this bad? Because the iPad is a closed device and doesn't encourage as much immediate hacking and interest as a open device does.
On a Mac, anyone who has the interest can fire up Terminal, learn a few Unix commands and be messing around. It encourages that because it's a open device.
The iPad has a high barrier to cross before one can get under the hood. This high barrier is going to discourage future youth from a interest in computers.
So why bother with custom silicon? By forgoing some features commonly found on other Cortex-A8 devices, Apple can likely squeeze more power out of the processor than others
There's also economies of scale at play here. If you own the chip design, you can directly benefit from any drops in production costs further down the line. Consoles have chip designs owned by the manufacturer for this very reason, and hence their ability to continuously drop the hardware price.
If the iPad is going to sell in the tens of millions then owning the chip design makes a lot of sense.
Having said that, I thinking I'm going to hold off until the 2nd gen iPad is released. I bought an 1st gen iPod touch and regretted it. The later models solved all of the iPod touch's short-comings and I fully expect the iPad to follow a similar path.
I'd love to see you try to explain why Apple's A4 chip, of which you have no knowledge, is capable/incapable of driving Apple's next take on multi-tasking in 4.0? (of which you also have no knowledge)
Current jailbroken iPhones can use Backgrounder, a feature that enables per-diem multi-tasking, with almost no impact on performance. Only battery life, which is a no-brainer/to-be-expected.
The 3GS has enough horsepower and RAM to run two apps at once with no noticeable drop in performance.
So where is the validity that a better and faster chip wouldn't be capable of what the current much slower chip already is?
LOL, so you think there is going to be true multitasking when:
-the iPad will be running the same OS as the iPhone so there will be no significant differences between the two devices
-the iPad has to power a higher res display
-the iPad will introduce more powerful apps that will be more resource intensive
If that was your argument then you are making a lousy one. The 3GS is a meaningless argument. There will not be a situation where the iPhone will have multitasking and the iPad won't. Chances are it will 've some kind of gimped, widget based where certain kinds of apps can be run in the background without the full UI being launched.
BTW, don't go off immediately saying that I don't what's inside the chip when the first two words I posted were "if true".
Who cares. If the device runs fast enough for its intended use I wouldn't care if there are a bunch of nano guinea pigs in there running the thing.
I'm thinking exactly the same thing. Why bother with GHz and core numbers, if the overall product is working as one would expect. (I know, it is stupid to ask this question in a geek forum