I keep on hearing from people that the A5X will be clocked the same as the A5? What I'd like to know is where people seem to get their sources from. Seriously, Apple almost doubled the battery of the new iPad. There is no way the Retina Display takes up that much power, considering how even with 4G LTE, battery life only goes down to 9 Hours. My theory to explain this is that the A5X is clocked higher, maybe at 2 GHZ. Apple has rarely, if ever, upgraded a product without upgrading the CPU, and I would think (not sure) that a quad-core GPU would need an enhanced CPU to feed it information.
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How do we Know the A5X Clock Speed?
- Thread starter iHuman1337
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The Retina display does take up that much power. It is driving 4 times the amount of pixels hence the 70% increase in battery life just for the display.
Also Apple does sometimes update a product without upgrading the CPU. Case in point, the iPhone 3G which utilized the same processor as the original iPhone. It is also the reason why the 3G ran like crap as soon as iOS 4 came out.
Well its the GPU thats supposed to be driving the extra resolution and may take more power... the display is definitely the bulk of it though.
CPU wasn't really a bottle neck for the iPad 2, I expected it to be improved a bit as much for vanity as anything else but am not too surprised by the reports that its the same.
It does seem like the upgrades may have merely offset the demands of the resolution without improving its capabilities much otherwise. I guess we'll see.
CPU wasn't really a bottle neck for the iPad 2, I expected it to be improved a bit as much for vanity as anything else but am not too surprised by the reports that its the same.
It does seem like the upgrades may have merely offset the demands of the resolution without improving its capabilities much otherwise. I guess we'll see.
No one outside of Apple knows for sure if the CPU clock speed has been increased or not. We'll find out this week.
Heat keeps me from thinking it's at 2ghz. My iPad 2 gets pretty damn warm after drawing in ArtRage or playing Infinity Blade 2 for a little while, I can't imagine that they added 2 more GPU cores AND doubled the clock speed. It could be higher than 1ghz, but I would say no more than 1.5 if that.
But video never seemed to take up that much power in the first place. The iPad 2 got ten hours of video easily, whereas with games, that number will probably go down significantly.
Besides, if you look at the transition between the 3GS and the 4, the battery never increased like the iPad did.
But Apple has huge competition this time around. Not from just Android, but from Windows 8. I'm not sure what competition was like back then.
And you said the iPhone 3G ran like crap when iOS 4 came out, so I think Apple would've learned their lesson and updated the CPU accordingly.
Not really. Apple will save the A6 for Cortex-A15. They seem to only bump up the A# when they move on to a new architecture.
The display takes up more power than you think. Adjust the brightness from 100 percent to 50 percent can be a good demonstration of that. For instance, when I fly on long flights I can watch nearly eight hours of video (length of my flight) on the lowest brightness setting and still have 60% of battery life left.
If I had it anywhere above 50% brightness I would have been in the 20% battery life rang.
That's pretty normal though, and what Apple probably uses for battery tests. And you can watch a movie for ten hours, but I doubt I can play Infinity Blade II for that amount of time, which leads me to suspect CPU might be a reason for this massive battery upgrade.
Also, (I'm no graphics expert) why would a Retina Display take up more battery? Sure, there are 4x the pixels, but the pixels are also 4x smaller, meaning there would be less energy needed to power them. I would be more worried about GPU than battery life. If I'm wrong, please don't flame me, I was just speculating.
Finally, the transition between the 3GS and the 4 didn't require much difference. In fact, going by Wikipedia, they were almost the same.
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I've heard a couple of reports stating the CPU is running at 1.5ghz but then I also heard a lot more reports it's still clocked at 1ghz.
http://www.trustedreviews.com/news/new-ipad-secrets-details-missing-from-apple-s-specs
http://www.newelectronics.co.uk/electronics-news/ipad-3-features-1-5ghz-dual-core-a5x-chip/40824/
http://www.trustedreviews.com/news/new-ipad-secrets-details-missing-from-apple-s-specs
http://www.newelectronics.co.uk/electronics-news/ipad-3-features-1-5ghz-dual-core-a5x-chip/40824/
It won't even be close to that. And they'd most definitely have mentioned it.
Here's a few likely reasons why the iPad 3 needs so much more power:
1) More powerful backlight for the retina display
2) Twice as many GPUs as before, and they'll be more active overall
The A5X's processor will be either unchanged, or 1.2GHz. The GPU will also be clocked the same as in the iPad 2, give or take 10MHz or so.
I think Apple said something about twice as fast as iPad2.. I'm not sure if they were implying graphics only - but they seemed to say something like 4x faster than iPad2 for graphics.. So if they are claiming twice as fast overall than iPad 2, the CPU could be clocked up to 1.5ghz to achieve this.. Nobody knows until benchmarks come out.
The tick tock model is an intel thing (architectre and process shrink), it's irrelevant here. Apple does incremental upgrades, considering the whole product design, with whatever's available to them. Their yearly schedule won't always sync up with supplier's schedules. e.g. The ARM A15 wasn't available, so it didn't go in, but I'd guess they did bump the speed a bit. We'll see. I don't know what Apple would do if it was actually feasible to design a product with all of the hoped for upgrades.
Problem with existing architecture... Say the iPad2's A5 clocked at 1.0ghz is a 1:1 ratio of speed and efficiency.
Clocking it to 1.2ghz to 1.5ghz is not a linear 20 to 50% increase in speed, you tend to experience diminishing returns after that initial 1:1 performance ratio.
The only way to get real speed increases is by always jumping to the next-gen architecture, which the A15 is not ready for prime time yet - so we are probably facing a small "overclock" if you will to the A5 to get small performance gains.
Clocking it to 1.2ghz to 1.5ghz is not a linear 20 to 50% increase in speed, you tend to experience diminishing returns after that initial 1:1 performance ratio.
The only way to get real speed increases is by always jumping to the next-gen architecture, which the A15 is not ready for prime time yet - so we are probably facing a small "overclock" if you will to the A5 to get small performance gains.
I've also wondered why the screen itself would use that much more power. Given some pretty basic laws of physics about energy, the screen itself shouldn't use any more energy, unless it produced more light or heat. I do think that the iPad 3 (I'm just calling it that Apple, deal with it!) will run very hot when stressed out, but it shouldn't emit anymore light, and thereby not use up that much more battery.
The GPU is another story, and IMO this, not the screen itself, ought'a be what will use most of the extra juice. I'm no techie, though, and I could (probably am) very wrong
The GPU is another story, and IMO this, not the screen itself, ought'a be what will use most of the extra juice. I'm no techie, though, and I could (probably am) very wrong
I've also wondered why the screen itself would use that much more power. Given some pretty basic laws of physics about energy, the screen itself shouldn't use any more energy, unless it produced more light or heat. I do think that the iPad 3 (I'm just calling it that Apple, deal with it!) will run very hot when stressed out, but it shouldn't emit anymore light, and thereby not use up that much more battery.
The GPU is another story, and IMO this, not the screen itself, ought'a be what will use most of the extra juice. I'm no techie, though, and I could (probably am) very wrong
Higher resolution = More load on the GPU = More power consumption.
Just look at the size of new GPUs for PCs that hit the market these days. Some of them consume need their own power supplies and consume more juice than the all other components combined. And another bi-product of anabolic graphic cards is heat.
It will be interesting to see whether the iPad will run hot gushing up polygons at resolutions I wouldn't even try on a PC.
I just figured out the answer - how we know the clock speed. Because I just watched that part of the Apple presentation. It was his wording - he talked about how great the A5 chip was, and then said that 4 times the pixels requires more graphical power, so they created the A5X chip. "What's the X for? Quad core graphics!" So if the only thing new abut the chip was the graphics, that means the CPU is unchanged. This is quite different than the introduction to the iPad 2, where when they talked about the A5 chip they talked at how much faster both it's CPU and GPU were.
An approximation can be made when the first unbiased benchmarks are published.
As A5X is most likely based on 32nm SOI, an increase in frequency is possible without an increase in power consumption. Apple's main focus was on graphics though so if there is an increase, it's not significant (around 1.3GHz would be my guess).
As A5X is most likely based on 32nm SOI, an increase in frequency is possible without an increase in power consumption. Apple's main focus was on graphics though so if there is an increase, it's not significant (around 1.3GHz would be my guess).
Undoubtedly a CPU/Graphics intensive game will tax the battery pretty heavily.
But you missed my point. The Display Panel uses more power than you think, you can prove this by simply adjusting the brightness. Play infinity blade at minimum brightness until battery dies, and then play it at maximum. You will see a noticeable difference in battery life.
I've also wondered why the screen itself would use that much more power. Given some pretty basic laws of physics about energy, the screen itself shouldn't use any more energy, unless it produced more light or heat. I do think that the iPad 3 (I'm just calling it that Apple, deal with it!) will run very hot when stressed out, but it shouldn't emit anymore light, and thereby not use up that much more battery.
The GPU is another story, and IMO this, not the screen itself, ought'a be what will use most of the extra juice. I'm no techie, though, and I could (probably am) very wrong
An LCD display works by shining a light through millions of tiny red, green and blue filters. Around and in between the filters are the various bits of support circuitry necessary to make the display work. My guess is that on the retina display there is more circuitry in comparison to the area of the filters and hence the display lets less of the backlight through. To overcome this Apple installed a more powerful backlight and that's the reason for the bigger battery.