Apple A5X quad-core confusion, explained | Hacker News Reader

Apple A5X quad-core confusion, explained

ubergizmo.com

47 pointsdazbradbury43 comments

http://www.anandtech.com/show/5072/nvidias-tegra-3-launched-...

Graphics comparison:

Tegra 3 (Kal-El) @ 300 Mhz: 7.2 Gflops

A5X (2 x Power VR SGX MP2): 2 x 19.2 Gflops = 38.4 Gflops

Actual GPU clock on Tegra 3 unknown (in this article) but if it was 400 Mhz that would be 9.6 Gflops which would be exactly 1/4 of the A5X.

Is the dual-core in the A5X faster than in the A5, excluding the GPU?

Unknown. We'll have to wait for some benchmarks to see the clock speed.

On Anandtech today they say the actual speeds may be 250 Mhz and 333 Mhz. The same math basically holds.

I wasn't very confused to start with. Is it fast enough? Yes/No? Yes.

Very hacker-like attitude indeed. /s

At the end of the day this is what counts. Is it fast or not. What else are more cores for if not for more speed and performance.

I don't like that attitude calling someone not hacker-like because he doesn't cares about cores! It's all about creating something better and that has nothing to do with counting cores.

http://en.m.wikipedia.org/wiki/Hacker_(hobbyist)

Actually it IS very hacker-like.

Hackers care about using the machine to DO (as in "hack") stuff. Faster, ok, better. Most top notch programmers could not care less if they have a state of the art CPU or not.

What it is not, is very tinkerer-like.

Tinkerers use the machine just to use the machine, and they eat precise specs for breakfast.

Interesting - I definitely believed there were four cpu cores in that chip yesterday. It'll be interesting to see what is made of this double speak, lord knows if someone like samsung pulled a trick like this the condemnation from the true believers would be severe.

Strange, maybe you read a bad reporting somewhere. I followed the presentation via Engadget live blog and did not get confused on this point http://www.blogcdn.com/www.engadget.com/media/2012/03/apple-...

GigaOM published a "quad-core" headline and I'm sure they weren't the only reporters who were confused.

"Quad-core" is a term very well established in the CPU market, and well understood by the public in that context. Using it to refer to a GPU feature is non-standard and just asking for confusion. Doing it as they did in that presentation, next to "A5X" (which the public understands to be the "CPU", only geeks know what a SoC is) IMHO borders on deliberate disinformation.

"Core" is a very well established term in the GPU market as well. I thought the way the spoke of it in their presentation was pretty clear.

http://www.google.com/search?client=safari&rls=en&q=...

No, it's really not. Neither NVIDIA nor AMD use it in their own marketing, nor does Intel for its Graphics parts. The tech press does, but (and this is important) only as a means to explanation via reference to the term from the CPU world. And even when they do, they have to throw in a ton of caveats about how "cores" don't match up between the very different architectures, etc...

Apple's use of the term "Quad-Core" in that slide is confusing. I don't see that there's any meaningful doubt about that. The more interesting thing is whether it was deliberately confusing.

"Core" isn't even really that well defined for CPUs, look at the controversy over whether AMD's new architecture is 4 clusters with 8 cores, or if you should really count the the clusters as cores but with two threads each.

A good way to do it might be to count the number of structures that can independently schedule memory operations, in which case AMD is correct to call their chips 8 core, but if you use that definition then the "512 core" GPUs are suddenly only 32 cores. Or you could count independent execution units so that the GPU is still 512 cores, but then your "4 core" CPU is now suddenly 12 cores.

"Core" is used in the context of the PowerVR SGXMP chipset in the iPad 3. See this Engadget article from January: http://egglets.com/news/2011/01/28/id-51851/sony-ngp-gpu-sgx...

> Neither NVIDIA nor AMD use it in their own marketing, nor does Intel for its Graphics parts.

Imagination Technology (the makers of the SGX 543MPWhatever), though, _does_. A particularly confusing usage; in this context it means 16 SIMDs. NVidia occasionally also refers to the Tegra 3's GPU as being 12 core; _they_ mean that it has 12 SIMD units.

Neither NVIDIA nor AMD use it in their own marketing, nor does Intel for its Graphics parts.

Well, that doesn't appear to be factual.

http://www.google.com/search?client=safari&rls=en&q=...

And the associated reporting that the public reads [1]:

  A5X processor is confirmed, quad-core graphics!

and

  Now we're talking about the quad-core graphics A5X. [...]

[1] http://www.engadget.com/2012/03/07/apple-ipad-3-liveblog/

Edit: another slide... http://imageshack.us/photo/my-images/23/4cg.png/ @ 28''30

Taking a term out of context and then sticking it next to another term doesn't make it clear. It makes it confusing. Think about terms like "irradiated food" (failed in the market) or "nuclear magnetic resonance imaging" (had to drop the N-word) which ran into exactly this problem.

You probably have some idea about how GPUs work, so the idea of having "multi core" ones wasn't shocking to you. Most of the people to whom that presentation was targetted don't have that context. To them, it sounds like "The Quad-Core A5X CPU enables faster graphics!", which is perfectly reasonable IMHO, and matches the use of Quad-Core in other contexts they know.

But Apple, of all companies, knows this already. They are masters of communication strategy. They picked "Quad-Core" deliberately, probably as an attempt to dilute the branding Tegra has already established with it. And that's sleazy.

It's not out of context. PowerVR advertises the SGXMP series as a multi-core solution: http://www.imgtec.com/News/Release/index.asp?NewsID=449

"The technology, henceforth POWERVR SGX543MP, is being delivered to customers in SGXMP2 (two-core) to SGXMP16 (16-core) variants."

I like to think of myself as more technologically aware than an average consumer, and I've never heard of PowerVR. The manufacturers of graphics hardware I do know never use cores in their marketing.

Nvidia often makes exotic claims about its SoCs; for instance that the Tegra 3 was faster than a Core 2 Duo (later retracted), and that the Tegra 3 provides "the fastest gaming" (it's beaten by the Apple A5 (iPad 2, iPhone 4S) and the Qualcomm S4 on most game-oriented benchmarks, sometimes substantially). Dubious claims are pretty common in the SoC business.

I don't think any one SoC rules all the benchmarks, which is why it's easy for these companies to cherry-pick the ones that make them look good. There is no one chip to rule them all... yet.

> Interesting - I definitely believed there were four cpu cores in that chip yesterday.

I have trouble understanding how that could be done, they clearly stated "quad-core graphics" as opposed to the A5's "dual-core graphics" (the A5 using a SGX543MP2 with the A5X probably being a SGX543MP4), there was no fudging around or tentative to make it anything but.

I was thinking you were joking and then I realized you were serious. Were you? Did you see how you used the same phrase to mean two different things?

  ... they clearly stated 'quad-core graphics'
  ... as opposed to the A5's *'dual-core graphics'*

All of Apple's messaging around the iPad and 4S are 'dual core' means two CPUs. And with the 'New iPad' (nobody calls it an iPad 3 I notice) they said the A5X with 'quad core graphics'. They are being imprecise in their messaging and since it is uncommon for them to be imprecise it seems to reflect they are perhaps a bit touchy about the Tegra-3's claim of being quad-core.

So it was painfully easy for a non-technical person to come away from both the announcement, and the 'features' on the web site, thinking that there are four CPU cores in the new iPad. We can debate if that was an honest mistake or a calculated risk, I expect it will turn out badly for Apple either way.

[1] "The dual-core A5 chip delivers even more power. ..." https://www.apple.com/iphone/features/

[2] "The A5X chip with quad-core graphics drives four times the pixels of iPad 2" https://www.apple.com/ipad/features/

Agreed. Apple generally hides tech specs, so when they do talk techie it's for a very specific reason.

I'm not sure where I read the specs yesterday - the ipad isn't of a lot of interest to me, so I wasn't doing something like following a live blog as suggested elsewhere.

As I was just browsing the print WSJ a bit ago I did find an excellent example of why people like me might be confused. Note in the picture the chart the WSJ published of the specs shows: Processor - Quad Core (new ipad) - Dual Core (ipad 2)

pic: http://desmond.imageshack.us/Himg69/scaled.php?server=69&...

You're right its a non-issue. Apple clearly states they have a quad core gpu. It's clear on their site and the tech specs state it has a dual core cpu and quad core gpu. Anything to get some traffic I guess.

Apple pulled a clever ninja word dice, knowing that most consumers don't really know or care what the difference is. The problem Apple faces is that in BestBuy, Target Etc.. you will have sales people that don't know a lemon from an orange yet will push whatever tablet has "Quad-Core" because it sounds better. With the use of the term Quad-Core Graphics Apple more or less guarantees that the average consumer looking at a Quad Core (Cpu) Android will think that is more or less the same as the Quad-Core (graphics) from the iPad.

Understandable however disingenuous it may be. What I found interesting was that people who should know better (I'm looking at you Bloomberg) got confused as well.

At least they didn't put in a dual-core CPU, a dual-core GPU, and call it a quad-core device.

Or claim it has 6 cores.

> (...) lord knows if someone like samsung pulled a trick like this the condemnation from the true believers would be severe.

Interesting, it seems to me that Apple gets far more scrutiny than any other company in tech.

> lord knows if someone like samsung pulled a trick like this the condemnation from the true believers would be severe.

True believers say that specs are for nerds (and so would I). The occasional benchmark results are interesting, though.

The last thing I remember about Samsung pulling a "trick" was comparing pixel density on PenTile and some other display type, with the accusation by some that X DPI on one doesn't equal X DPI on the other... and I didn't notice a backlash.

I didn't realize there was confusion. He was pretty clear about quad core graphics and the iPad site on Apple is pretty clear about quad core graphics but a dual core cpu.

Tegra 3 vs. A5 benchmarks (Transformer Prime vs. iPad 2) http://www.anandtech.com/show/5163/asus-eee-pad-transformer-...

BTW: Apple claims x2 GPU performance over iPad 2 - suggesting the doubling of GPU cores to MP4 is the only source of increased performance. Because the iPad 3 (?) has x4 the pixels of the iPad 2, half-speed seems expected (if using full resolution). The same thing happened for the first iPhone retina display, so not that surprising. It's likely game devs will use the same solution as on the xbox360: less than full resolution.

There is still much we don't know about the A5X. The A5 in the iPad (which is different from the iPhone 4S's and Apple TV's A5) is clocked at 1 ghz per core. The A5X could be clocked higher. We won't know until the benchmarks come out.

The A5X does have two additional GPU cores. They could be clocked higher or lower than the old GPU cores or the same. Again we won't know for sure.

We do know that the new iPad has a battery almost twice as a big as the iPad 2s. Clearly there is a lot more pixels and horsepower to push.

Just because a tablet has more or less cores won't tell you everything about its computational power. Some companies may go with more cores clocked lower, while others with fewer cores clocked higher. Others will focus more on GPU performance (and in having the GPU accelerate non-graphical tasks), while others will focus more on CPU power.

Ultimately Apple probably couldn't have gotten the battery life it wanted with a quad-core CPU and quad-core GPU at the same time. Apple clearly is prioritizing GPU power, as they have been pushing the iPad, iPhone and iPod Touch as portable gaming devices. Apple has also been pushing the GPU to be used for general computing purposes.

I wouldn't be surprised to see the A5X having faster core speeds for the CPUs.

Battery life is the biggest concern for mobile devices. Some companies are putting CPU power first, while others are putting GPU power first. This is good for consumers.

After all the bickering, he ends the article with

> The new iPad is a Dual-Core tablet with a graphics engine that is 2X the speed of the iPad 2

out of nowhere. 2X? He just provided evidence that the iPad 2 is 2x faster than Tegra 3 - it's obvious the new one must be at least 4x faster since it's driving four times more pixels (they wouldn't launch a new iPad that performs worse), and that would make it even more than 4X faster than nvidia.

He did not provide evidence that the iPad 2 is 2x faster than Tegra 3--rather, he showed that on one benchmark that isn't entirely relevant it performs twice as well. His theory is that the new model is 4x faster on that benchmark. But the real point is that the particular benchmark is of limited utility.

You must not have read the article.

I had to ... as patiently as I possibly could ... explain to a woman yesterday that her iPhone 4 was not 4G (LTE). I think people like her are who Apple target with this sort of marketing. Don't misunderstand, I don't believe Apple made users believe they were getting a 4G phone with the iPhone. I just think companies like AT&T, Verizon, Samsung and Apple word things in a manner intended to put their customers in a certain frame of mind.

It is worth noting that the new iPad has the same GPU as the Playstation Vita. I think that says something about the gaming performance implications for the chip. I doubt the Tegra 3 stacks up, because if it did, surely Sony, a company that needs great portable gaming performance, would have looked much harder at the platform.

no surprise apple is just pulling marketing stunts like always

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