

The iPad CPU: Details on the Apple A4 - profquail
http://www.maclife.com/article/feature/ipad_cpu_all_you_need_know_about_apple_a4

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pvg
This is less 'details' and more 'guesses'. There have also been (equally
unconfirmed) reports that it uses a different GPU (an ARM Mali).

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timdorr
I stopped reading after I noticed the word "likely" is used 7 times in the
single page article...

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risotto
Pure speculation on my part, but I wonder if Apple can and/or has baked
trusted computing into the A4 silicon.

By controlling this much of the hardware, Apple can make it next to impossible
to jailbreak their devices.

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blasdel
There was nothing stopping them before: both generations of iPhone / iPod
touch chips were bespoke SoC hardware too, just via Samsung.

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petercooper
The core of the piece:

 _The A4 is actually built around a CPU core based on the common ARM Cortex A9
CPU, a 32-bit core that comes in several different flavors, with different
numbers of cores. In typical cases, companies like Apple actually license the
CPU design -- rather than paying $278 million to acquire the whole company!_

If Arm Holdings could be acquired for $278m, I'm sure Apple would have done it
by now. Unfortunately for Apple, though, its market cap is actually in the
$2-$2.5bn range.

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wmf
The point is that Apple bought PA Semi for $278M. It would be unusual to spend
so much money for a processor company and then turn around and use off-the-
shelf ARM processors.

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rphlx
A PA VP told me Steve Jobs asked them to drop their nearly-finished Power
design immediately to build AAPL a custom ARM SoC; they said no, so he bought
them, to help them say yes. He probably could have poached their stars for a
lot less than $278M, but I guess he was in a serious hurry, or just viewed
$278M as not worth the hassle.

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hga
If he'd tried the "poach" approach, he'd probably not have gotten intact teams
and there would have been a _lot_ of unhappy people.

Buying the entire company almost certainly worked better, another sign that
Jobs "gets it" even without being a hardcore techie. A one of a kind, I think.

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rphlx
Perhaps. But if you look at the comps, PA investors got a sweet deal.

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tyrelb
I remember when Apple brought out the Macbook Air - and it sounded like a huge
partnership between Apple and Intel. What is the relationship going forward?

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sparky
I don't have any inside scoop here, but a huge partnership between Apple and
Intel and an ARM-based iPad are not mutually exclusive. Most people
acknowledge that, to get the kind of energy efficiency and battery life that
people are starting to expect in mobile devices, current x86 parts are not a
good solution. Nonetheless, we are stuck with x86 for anything that wants to
run most existing desktop/laptop software until we come up with a
virtualization, cross-compilation, or binary translation scheme that is
efficient enough.

If Apple wants to continue selling Mac Pros and Macbooks, they will probably
stay Intel for some time. Until Intel comes out with a part that can get Apple
anywhere close to the many hours or even days they require for their mobile
devices, Apple has no choice but to look elsewhere, and I can't see that as a
reason to end a partnership on desktop/laptop processors.

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rphlx
A 1.6GHz Intel Atom spanks an entire week of lunch money out of a 1 GHz ARM,
in terms of CPU performance. No doubt AAPL can mostly hide that with faster
SW, relative to Windows Vista/7. But I would hate to compile anything on A4,
whereas, a $200 Linux netbook is fine for most development.

IMO it's sad for something iPad's size to not have a reasonable native
development environment.

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wmf
_A 1.6GHz Intel Atom spanks a 1 GHz ARM_

Not necessarily; ARM claims that the Cortex A9 is the one doing the
superscalar out-of-order spanking and I'm inclined to give them the benefit of
the doubt.

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chadaustin
I'd love to see citations on both rphlx's and wmf's claims. Not trying to
sound mean - I'm honestly interested in the future of low-power computing and
I kind of hope ARM wins.

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pieter
Here is one link:
[http://perspectives.mvdirona.com/2009/09/16/ARMCortexA9SMPDe...](http://perspectives.mvdirona.com/2009/09/16/ARMCortexA9SMPDesignAnnounced.aspx)

Also Anandtech on the Cortex A9:
[http://www.anandtech.com/gadgets/showdoc.aspx?i=3714&p=3](http://www.anandtech.com/gadgets/showdoc.aspx?i=3714&p=3)

and the pages around that.

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mru
I read somewhere that the A4 has an ARM MALI graphics processor, not an SGX.

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wmf
That guy _also_ has no idea what he's talking about.

