Investigation on iPad 3 overheating - Page 1
Forum section: electronics / general

author: jackbob
author_rank: Regular Contributor
timestamp: March 26, 2012, 06:50:21 am
content: It would be cool to see Dave do a tear down of an iPad 3 and see why it is the new iPad is overheating. Bad thermal design? Dave did a tear down of the kindle fire it would be interesting to see the same for the iPad 3 and hear Dave's opinion if he can get his hands on one.

author: IanB
author_rank: Super Contributor
timestamp: March 26, 2012, 07:41:14 am
content: It's most likely a software problem. The iPhone had similar issues after the upgrade to iOS 5. It was supposed to be fixed in later updates.The iOS devices get their long battery life by spending as much time as possible with the CPU in an idle state and nearly all programs suspended except for a critical few. A bug can cause a program to get into a CPU bound loop and that both eats battery power and makes a lot of heat. When an iPhone got into that state it would run the battery flat in an hour and turn into a pocket warmer at the same time.

author: wkb
author_rank: Super Contributor
timestamp: March 26, 2012, 07:42:40 am
content: Overheating? What overheating?Overheating means going out of spec, and that is not what is happening as far as I can tell from all the rambling from the clueless. In some use cases it gets warmer than the previous versions but that is all. It is not cooking itself or its user to death...It is utter nonsense for Dave to go and wreck a perfectly fine piece of hardware IMHO.

author: T4P
author_rank: Super Contributor
timestamp: March 26, 2012, 08:23:48 am
content: 54C in your hand is HOT !It would be okay if it was on the floor , but if it's in your hands , that's UNACCEPTABLE .And the Pad3 is bloody OVERexpensive .

author: MrPlacid
author_rank: Frequent Contributor
timestamp: March 26, 2012, 10:50:28 am
content: Quote from: Dave.S on March 26, 2012, 08:23:48 amI thought it was 47C (116F).

author: T4P
author_rank: Super Contributor
timestamp: March 26, 2012, 01:37:12 pm
content: Quote from: MrPlacid on March 26, 2012, 10:50:28 amNot alot , but still is a shitload !

author: wkb
author_rank: Super Contributor
timestamp: March 26, 2012, 01:39:55 pm
content: Quote from: Dave.S on March 26, 2012, 08:23:48 amWho cares what you call OVERexpensive? Not the x million Apple-addicts that already bought one...

author: im_a_human
author_rank: Regular Contributor
timestamp: March 26, 2012, 07:31:07 pm
content: Apple have a reputation with making devices that overheat and go out of safe spec. I used to be a dillusioned apple fanboy once.

author: Ajahn Lambda
author_rank: Regular Contributor
timestamp: March 26, 2012, 07:51:10 pm
content: Quote from: wkb on March 26, 2012, 07:42:40 amIt's not like it's a Fluke or Agilent instrument. I say have at it (with a hammer!).How about if he were to take one apart, give us a review, then re-assemble it and give it away to a subscriber? Win win?

author: PStevenson
author_rank: Regular Contributor
timestamp: March 26, 2012, 07:58:46 pm
content: Quote from: wkb on March 26, 2012, 01:39:55 pmI think no matter what the price, if you're an addict of something you will buy one. so really if you're an addict of something you're no longer objective as to what is overpriced. they are overpriced but that aside if you think apples stuff don't overheat then you need to look at the cases where all sorts of their merchandise has overheated to the point of combustionhttp://www.telegraph.co.uk/technology/apple/8922888/Exploding-iPhone-investigated.htmlto link to a recent onepersonally I get what does the most for the least as reliably as possible - so for computing I use a PC, for portable music I use an iPod, for mobile phone I use a sony, for reading on the go I have a kindle cause it was the cheapest, people who get sucked into this brand name loyalty crap just shut off avenues and miss out on things that might work better for themas for the OP - I would love to see dave do a teardown too, I don't think he would wreck it, he hasn't wrecked anything else he's taken apart, unless it was on purpose of course.

author: jackbob
author_rank: Regular Contributor
timestamp: March 26, 2012, 09:24:27 pm
content: I hear it's only when certain apps are running which makes it obvious it's either the CPU or the ram possibly both. Although the ram shouldn't get nearly that hot. Not only does it make it uncomfortable for the users which is very bad product design but it may not be good for the components. It has many problems including shortening the battery life and stressing out other components around the heat. It has to dramatically reduce the performance and life of the components. The cause of the problem is what I want to find out, maybe they designed it different and the CPU is closer to the case or maybe its bad heat dissipation design or a bad design that pushes the capabilities of the components. I read someone posted its software, it is possible that could cause the CPU to heat as it does which definitely should be fixed if it is the problem. However with a good design the iPad should be able to dissipate the heat even if it does get hot

author: IanB
author_rank: Super Contributor
timestamp: March 26, 2012, 09:58:36 pm
content: Quote from: jackbob on March 26, 2012, 09:24:27 pmThere are some limits here. The battery in the new iPad contains twice the energy of the previous model and the case is the same size. If you use up that energy slowly, all is good. However, if you use up the energy fast, for example by doing heavy computations and graphics, then that energy is going to be converted rapidly into heat inside a small space. The laws of physics say the heat has to escape somehow, and it can only do that by heating up the case so the heat can be transferred to the surroundings. Only two variables are under the designers' control: the rate of heat liberation, and the amount of external surface that heat is dissipated through.Remember that a device only a few mm thick that can play 1080p video and HD video games is an amazing piece of kit. You would normally have found a bigger case and a fan in things that can do that kind of computation. Technology is a wonderful thing, but sometimes physical constraints leave you few options when you are up against the limits.

author: jackbob
author_rank: Regular Contributor
timestamp: March 26, 2012, 10:18:08 pm
content: I can see why it gets that hot the normal temp of a NetBoot processor easily can hit 116f but they should design the case in such a way that allows air flow or has more surface area to dissipate the heat. I would like to see the inside of one how they designed it. They could have put in a tiny blower on the CPU heat sink. There are blowers so small that there is no reason they couldn't put one or at least a vent by the CPU.

author: T4P
author_rank: Super Contributor
timestamp: March 26, 2012, 10:23:06 pm
content: Nah . If a tablet needs a fan , the fan will easily draw more then the tablet itself .But remember heat = power wasted . Thumb of rule there .It's not really a wonderful thing for 1080p videos , with a optimus 3D , 3DHD-720P , Full HD1080P Playback AND Recording .How's that for a phone not much thicker and heavier then my optimus black ( which is the thinnest and lightest smartphone on the market )Really , i find 3D bollocks but oh well , that sure makes a shitload MORE sense then the iPhone's which cost like 700$(of course , with a HSDPA plan) for a 16GB model and didn't even have dual cores ( back then , iphone 4S took too long )We all need to remember if something is hot = hungry and no good .

author: IanB
author_rank: Super Contributor
timestamp: March 26, 2012, 10:27:13 pm
content: You can see the inside of an iPad if you look at a teardown. The space inside is almost entirely taken up with the battery, then the screen. The circuit boards are tiny and squeezed into the small gaps that remain.I just did a bit of investigation and there doesn't seem to be much evidence that any problem exists. The case gets warm when doing processor intensive tasks (but not hot), and if it gets too warm it automatically switches off until it cools down.I don't think you want to have vents or fans in such a device as dust and fluff will just get inside and clog everything up. A fully sealed case is exactly the right solution for long term durability.I have an iPhone 4 and I observe it does get a little warm when hammering it; but this is "warm" not "hot".Since I am likely to get one of the new iPads I will find out for myself how warm it gets. I'm not too worried about it though. I think a non-issue is being spun into a story to make journalistic headlines.

author: jackbob
author_rank: Regular Contributor
timestamp: March 26, 2012, 11:00:52 pm
content: A fan is a little much but it would help out a lot you can get fans as small as a couple watts and if ou control it by temperature it would be perfect. Space for a fan would be a huge issue though. But the old iPads never got so hot. I'm wondering if the new iPad is layer out differently like the position of the CPU and such. Even though it may be normal ( I know CPUs can get hot ) if people are complaining then it scares away potential buyers from wanting one. They should have modes on the iPad that allows to increase or decrease performance when needed. Because wasting that much power on heat has to drain the battery quick. By allowing to set the performance you could increase battery life and decrease wasted heat when it is not needed. Then increase performance when you need it for running larger apps or hd video.

author: IanB
author_rank: Super Contributor
timestamp: March 26, 2012, 11:52:03 pm
content: In terms of CPU usage and performance, these devices only do what you ask them to do. For instance the iPhone remains quite cold for all normal uses. But if you spend an hour or two playing interactive games on it like Angry Birds then it gets warm (and drains the battery rather quickly). It's your choice whether to play intensive games on it or not. That is in effect your performance switch--you do power hungry things with it, it consumes more power; don't do those things, the battery will last for days.Most likely the iPad warm temperatures come from playing 3D games in HD for long periods. That's going to max out the power consumption. You can't just decide to play HD 3D games in low power mode, as the games then wouldn't play.

author: jackbob
author_rank: Regular Contributor
timestamp: March 27, 2012, 12:04:27 am
content: Most HP laptops and computers offer such a feature. I have an iphone 4 and i have to say the battery life is very impressive when i have my screen dimmed (that is until you use 3g, then it lasts like 5 minutes) the 3g totally drains it quick. But just beacuse your playing something that pushes the cpu hard doesnt mean you cant tune it down. You can reduce resolution, in some cases speed, and some features in the program, as well as screen brightness and many other luxuries that are not necessary but take a lot of cpu power. This would probably take some adjusting to the apps too. It can be the difference between 2 hours of battery life and say 10 hours

author: markus_b
author_rank: Regular Contributor
timestamp: March 27, 2012, 08:32:49 am
content: I think this is a general problem of these modern devices. There is a large difference in power consumption between normal and full feature usage. My SGS2 phone is the same. If I use it normally it stays cool and tha battery lasts for days. But if I play a 3d game, taking full advantage of the 3d GPU it gets very warm and the battery drains in 2h or so. Even if plugged-in the battery runs out (albeit slower) as it need more current than the power adapter can supply.This is probably the biggest challenge for the hardware part of these devices in the future, how to increase CPU/GPU power in the same power envelope. It is clear that we are already at or beyond what works out in the field.

author: T4P
author_rank: Super Contributor
timestamp: March 27, 2012, 07:44:12 pm
content: Quote from: IanB on March 26, 2012, 10:27:13 pmAny mobile device that switches off is no GOOD !

author: T4P
author_rank: Super Contributor
timestamp: March 27, 2012, 07:46:43 pm
content: Quote from: markus_b on March 27, 2012, 08:32:49 amAnd if you didn't notice the SGS2 gets very hot here .So if you didn't feel the SGS2 getting hot there , the NEW IPAD is going to just get very HOT !

author: T4P
author_rank: Super Contributor
timestamp: March 27, 2012, 07:47:37 pm
content: Quote from: jackbob on March 27, 2012, 12:04:27 amALL Laptops and computers have such a feature .It's simply because of a fact , why do other phones survive a day with HSDPA turned on ?It's because , APPLE SUCKS ! GET IT BOYS !

author: G7PSK
author_rank: Super Contributor
timestamp: April 03, 2012, 12:57:35 pm
content: I read some where that it was the bottom left hand corner that gets warm on the iPad and that is also where the power control circuitry is and that is why it feels warm it is where most people hold the device.

author: T4P
author_rank: Super Contributor
timestamp: April 03, 2012, 04:58:09 pm
content: Quote from: G7PSK on April 03, 2012, 12:57:35 pmPoor thought going into design , as it is .Looks like the boost converter is not done properly anyway or the processor is drawing quite big amounts of power and they used the same boost converter as the pad 2