# Benchmarks for the A4 CPU



## enon (Feb 12, 2010)

I want to know how slow this thing will be. Maybe equivalent to a 900Mhz Intel Pentium M? 

Browsing the web on the iTouch is no fun. Will it be the same for the iPad?


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## chas_m (Dec 2, 2007)

Have you thought about, I don't know, watching the keynote?

They do an extended demo of the iPad CPU there. Looks pretty smooth on a wide variety of tasks.

Here's another report by someone who has *actually used one*, Andy Inhatko of the Chicago Sun-Times:
Hands-on with the Apple iPad – it does make sense :: CHICAGO SUN-TIMES :: Andy Ihnatko

Speed does not seem to be a concern with any other review I have seen from someone who has *actually used one.*

The "secret" seems to be that while the A4 chip is "only" rated a 1GHz, Apple has augmented it with a full "system on a chip," meaning it can "offload" some specific duties (like graphics, MPEG4 decoding, etc) to subsystems.


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## Trevor... (Feb 21, 2003)

I don't see why it would perform much differently than any of the other virtually identical ARM/PowerVR based ASIC's


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## vfr (Jul 22, 2009)

Peering into crystal ball:

It will be faster than an iPhone 3GS, but slower than a current MacBook.

:-D


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## chas_m (Dec 2, 2007)

Trevor... said:


> I don't see why it would perform much differently than any of the other virtually identical ARM/PowerVR based ASIC's


Because it's not JUST an ARM chip with PowerVR added, otherwise Apple would have just bought an ARM chip.

Instead, they brought the ARM design in-house to remodel it. I have no idea what they did, but they definitely did SOMETHING different.


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## Trevor... (Feb 21, 2003)

It just isn't that sexy, 

ASIC's in mobile applications are used to reduce chip count, the higher the chip count the larger, more complicated and thicker the PCB and the greater the potential points of failure. This also opens the door to reduced power consumption as redundancies can be eliminated. 

Most mobile chipsets already incorporate a modern ARM core and the functionality found in a Northbridge, These however are rarely powerful enough, so another processor is added.

The iPhone for instance has an 300mhz ARM926 processor built-in to the Infineon baseband controller - which does practically nothing, the Motorola Q has Qualcomm 6500 chipset with an ARM processor and an additional Intel Xscale ARM processor on which Windows Mobile actually runs.

The A4 puts the iPhone platform on a single chip, it is unlikely to be anything more grandiose.


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## fyrefly (Apr 16, 2005)

Trevor... said:


> The iPhone for instance has an 300mhz ARM926 processor built-in to the Infineon baseband controller - which does practically nothing, the Motorola Q has Qualcomm 6500 chipset with an ARM processor and an additional Intel Xscale ARM processor on which Windows Mobile actually runs.
> 
> The A4 puts the iPhone platform on a single chip, it is unlikely to be anything more grandiose.


The iPhone 3GS has an ARM A8 that runs at 600Mhz.

AnandTech: The iPhone 3GS Hardware Exposed & Analyzed

And the A8 runs at 1Ghz. Plus it's been tweaked by Apple. I'd assume that the iPad will feel doubly fast to the iPhone 3GS. That's pretty great.

The point is, no-one knows about what the A8 can do right now 'cept Apple. When the iPad comes out in the next 4-5 weeks, we'll get a better sense based on reviews, benchmarks and teardowns.

And ARM A8 or Apple A4 isn't gonna blow the doors off of an i5, but it could probably give the ATOM a run for it's money. Especially if it can be scaled to be multi-core.


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## minnes (Aug 15, 2001)

I thought the A4 was based on the ARM Cortex A9, the next generation ARM up from the iPhone 3GS?


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## Trevor... (Feb 21, 2003)

Read what I said again,

The 300mhz ARM926 is built-in to the BASEBAND - it isn't the application processor. 

The issue that bedevils smart phones is that the chipsets that are powerful enough to not require a stand-alone application processor such as the Qualcomm MSM7600 are extremely expensive and marrying an external processor to a mainstream mobile chipset, such as the Infineon S-Gold is more cost effective even with the redundancies. The same chip is used on a stand-alone basis in mid-range LG handsets for example. 




fyrefly said:


> The iPhone 3GS has an ARM A8 that runs at 600Mhz.
> 
> AnandTech: The iPhone 3GS Hardware Exposed & Analyzed
> 
> ...


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## monokitty (Jan 26, 2002)

Does it really matter?

If it runs what the iPad is meant to run, the benchmarks or what the A4 is 'equivalent' to is a moot point.


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## chas_m (Dec 2, 2007)

Indeed. <puffs pipe thoughtfully>


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## fyrefly (Apr 16, 2005)

minnes said:


> I thought the A4 was based on the ARM Cortex A9, the next generation ARM up from the iPhone 3GS?


ARS is saying that's what people thought at first, but now they're thinking more that it's an A8 stripped of a bunch of frills.

AppleInsider | iPad's Apple A4 CPU is feature-stripped ARM Cortex-A8 - report


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## EggWhite (Feb 1, 2009)

*User Name*



Lars said:


> Does it really matter?
> 
> If it runs what the iPad is meant to run, the benchmarks or what the A4 is 'equivalent' to is a moot point.


Of course it matters. You don't think developers will be able to do more with a faster processor.


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