iPad 3 'Heatgate' drama is completely overblown

iPad 3 'Heatgate' drama is completely overblown

Summary: Yes, the iPad 3 runs warmer than the iPad 2. But it's simply a consequence of the Retina display's lower light efficiency and power efficiency. Comes with the territory folks!

TOPICS: iPad, Mobility

Much has been written about the increase in heat emitted from the iPad 3 with some tests claiming that it runs as much as 10 degrees Fahrenheit hotter -- while running GPU-intensive tasks -- than the iPad 2.

Late Monday evening Engadget stoked the fire with a post claiming that the new iPad burns 10 degrees hotter than its predecessor accompanied by thermal imaging photos of the iPad 3 and 2 side-by-side:

Engadget - the new iPad burns 10 degrees hotter than its predecessor - Jason O'Grady

One of the loudest complaints came from the venerable Consumer Reports which claimed that the iPad 3 hits 116 degrees while running games -- again using thermal images to support its case.

Consumer Reports - iPad 3 hits 116 degrees while running games - Jason O'Grady

Cue the #heatgate hashtag!

Having been burned (pardon the pun) by CR's scathing reviews in the past (you'll recall the CR was one of the most vocal of the iPhone 4 detractors during the Antennagate fiasco with the iPhone 4 in July 2010). Apple was quick to nip this one in the bud, with Apple PR’s Trudy Muller telling AllThingsD:

The new iPad delivers a stunning Retina display, A5X chip, support for 4G LTE plus 10 hours of battery life, all while operating well within our thermal specifications. If customers have any concerns they should contact AppleCare.

[Don't you love how Apple buries the response in the middle of a commercial? Geez.]

Ray Soneira, President of DisplayMate Technologies Corporation, thinks that the "overheating" claims are overblown and I agree.

I played games on my iPad 3 for about two hours straight last night while writing a review of five games that push the iPad 3’s Retina display to the limit -- and my iPad never got too hot to touch. It was definitely warmer than my iPad 2, but not unusually hot, especially for how much I was pushing the quad-core GPU and the Retina display.

For his part, Mr. Soneira thinks that the additional heat is simply due to the fact that the iPad 3 has to drive four times the amount of pixels of the iPad 2 double the amount of LEDs to light it up. In his excellent display technology shootout between the iPad 3, iPad 2 and the iPhone 4 Soneira notes that the iPad 3 has much lower display power efficiency:

The new iPad uses 2.5 times the Backlight power of the iPad 2 for the same screen Brightness. As discussed above that results from the TFT transistors in the LCD blocking much more of the light at higher ppi. On the other hand, the highest ppi iPhone 4 is the most power efficient display of all because it uses Low Temperature Poly Silicon LTPS, which is much more efficient than amorphous silicon in the iPads. All of this points to the need for the IGZO display technology discussed above, which is more efficient and lower cost than LTPS. It should be in production shortly, and is the first in a whole series of enhanced Metal Oxide semiconductors for LCD and OLED displays.

The highest ppi iPhone 4 is the most power efficient of all because it uses Low Temperature Poly Silicon LTPS (see above).

The number of Backlight LEDs has roughly doubled (from 36 to an estimated 72 to 82), so the Backlight power has approximately doubled. Since the display normally consumes about 50-60 percent of the total Tablet power, the new iPad needs at least a 50 percent larger battery. In fact, the battery increased from 25 to 42.5 watt hours, a 70 percent increase. Our measured Backlight power for the new iPad is 2.5 times the iPad 2 for the same screen brightness. In spite of the larger battery the running time at Maximum brightness in our tests was 5.8 hours, 20 percent less than the iPad 2‚s 7.2 hours. But at the Middle brightness slider setting, which is closer to typical user settings, the running time was 11.6 hours, which is almost identical to the iPad 2, indicating that Apple has used an appropriately larger battery (and confirms Apple‚s 10 hour claim).

Here's the data for Backlight Power and Battery Running Time from Soneira's display technology shootout.

The bottom line is that the iPad 3 backlight consumes 2.5 times as much power as the iPad 2 for the same brightness (luminance) due to the higher number of pixels per inch (ppi). The Retina display LCD has a lot lower light efficiency and therefore power efficiency.

According to Soneira, the iPad 3's LCD panel has 72-82 LEDs, which is approximately twice the amount of LEDs as found in the iPad 2. The iPad 3's LEDs give off 2.5 times as much heat as the iPad 2 as will the battery and power electronics.

He goes on to say that when the iPad 3 display is set for maximum brightness the display consumes about 65% of the devices total power, which plays a major roll in its thermal budget.

Both my new iPad and my iPad do not run excessively warm (let alone hot). As expected, I can feel that the new iPad is a bit warmer than the iPad 2, but they are both fine. Also I run mine at maximum Brightness for testing (which generates the most power and heat), whereas most people will run with a lower setting - it comes at the Middle slider setting from the factory. At the Middle slider setting the Backlight consumes only 36% as much power as at Maximum, so that is only 36% of the heat also.

It's certainly possible that CPU and GPU will heat up during extensive gaming, but the major power difference between the iPad 3 and iPad 2 is the Retina display.


Now, the issue won't be overblown if it results in massive hardware failures, but none have been reported (at least that I'm aware of) because it's just too early in the product lifecycle to know. And we're not likely to to have a definitive answer for several weeks or months to come.

Don't be surprised if someone runs a GPU hogging app continuously to see if the iPad 3 will melt or catch fire. Someone will do it and it will probably make it onto all of the cable news shows.

I would be shocked however if the additional heat was a genuine design issue. It's not out of the realm of possibility that there could be a production problem affecting a small percentage of the first batch of iPad 3s, but I doubt that it will result in a recall.

Apple announced that it sold 3 million iPad 3s on opening weekend and if the failure rate was 0.1% then that would translate to 3,000 defective iPads in the first batch -- not terrible by large-scale manufacturing standards.

I'm curious if the thermal issue will be exacerbated by putting the iPad 3 in various "full body" cases. As for me, I'm going to stick with a simple Smart Cover on my iPad 3 -- at least while it's running.


Topics: iPad, Mobility

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  • My Android tablet gets hot

    I have an android Vizio tablet and it can get hot I have noticed. I haven't played with the new iPad, so I can't verify the comparison, but I agree that it is overblown. If people start getting 3rd degree burns, then I can see some lawsuits coming.
    • Agreed

      My iPhone 3GS gets hot if I play games intensively, especially when connected to the mains.

      My htc 7 Mozart gets hot if I play games intensively, especially when connected to the mains.

      My htc Sensation gets if I play games intensively, especially when connected to the mains.

      Are any of them about to burst into flames? No
      Are any of them too hot to hold? No
      Are any of them uncomfortable to hold? No

      You just notice that they are warmer than usual.

      Given the restricted amount of cooling you can fit into a tablet or smartphone, it isn't surprising that they get warm or very warm when you push the processor and graphics hard. The battery discharging at a high rate also generates heat.

      It sounds like the reactions of some users are overblown.

      (And this from somebody who has no inclination to buy an iPad.)
    • Why is ADMITTING a problem considered to be "Drama" and "Overblown"

      Yes, the problem doesn't affect all users (both our iPads are absolutely perfect). Yes, there are specific situations that can magnify the issue. But NO, downplaying the issue doesn't mean the problems no longer exist.

      This is what bothers me most about Apple media. When an issue arises then rather than presenting problem they instead become Apple's personal PR team and try to spin the story before even giving it enough time to gather data. (it's only been a week! and a well reported issue from actual users is dismissed as "Drama" and "overblown"?

      Think about the Windows 8 tablets that actually have a fan in them. All we need is a single incident report and the opposing "fans" and media will latch on to that one story about MS Tablets overheating until Windows 9. But since it's Apple then all incidents are dismissed as whining or trolling. C'mon. Just because we can explain a problem doesn't mean it no longer exists. The MEDIA should be the first to acknowledge that.
      • Agree completely

        If there is tech news, whether that is a difference in product performance, battery life, or product temperature, then tech journalists are not wrong to report it.
      • You're right about the spin

        [i]just because we can explain a problem doesn't mean it no longer exists[/i]

        That's a perfect spin scenerio - Yes they're getting hot, so don't deny that, just spin it as it's not "that hot", and "part of the design"
        William Farrel
      • The problem is ...

        ... there really is no problem with the design. Apple responded that it's operating within design specifications. In other words, it's doing what they expected it to do.

        So, why is it some kind of crime for Apple to state that? Do they need to start recalling perfectly good iPads simply because they're a little warmer (but, again, within spec) than the previous model?

        Yes, obviously if they start bursting into flames and scorching users or igniting forest fires, Apple would need to recognize (admit to) and address the problem.

        But, so far, people have just noticed that they get about 10 degrees warmer. Oooh. Gee, my black car gets hotter on a sunny day than a white version of the same car. Maybe I should alert the media and hold a press conference to announce that I'm initiating a class action suit against Ford because they should have warned me about this obvious design defect.

        Seriously, I'm all about companies being honest when there's a problem. But, so far, this isn't a problem. It's a different model with different operating parameters. And the science of the display technology more than logically explains why the new iPad runs warmer.

        To report otherwise would be sensationalizing a non-issue. Then again, that is what today's media survives on, so I really don't expect them to do otherwise.
      • Because admitting to a problem could hurt sales.

        Why is ADMITTING a problem considered to be "Drama" and "Overblown"? The answer is surprisingly simple. Any problem a manufacture concedes to becomes an arrow in that manufacture's competitors quiver. I don't care if you are talking about tablets, cars, or fruit juice, this rule is applied by all business. There are exceptions of course, if your product is killing people it is generally better to come clean sooner rather than later, while explaining what steps you are talking to make sure it does not happen again.
      • It's the word choice used in the reporting

        but you already knew that.
      • Downplaying?

        It's not a problem. It's physics. Are we going to blame Apple for thermodynamics now?
      • The opposite has happened

        Sorry but you have it backward. There were dozens of stories talking about the new iPad running excessively hot last week. It was after all the "overblown" media reports trying to get page clicks that stories came out that actually did test to show it was overblown. I would be being extremely generous if I said I had seen half as many stories down playing this as I have playing it up.
    • BS! It's not over lbl

      BS! Its not overblown it's a real problem. Apple is full of crap when they say it's
      Johnny Vegas
      • Supporting evidence?

        I am happy to believe you, but where is your supporting evidence? Studies? reports of injury or malfunction? Anyone complaining that they had to put the iPad down and couldn't use it due to heat?

        Anything? Anything?

        Beuller? :)

        To be clear, there may be a problem and I am not saying there isn't. If there is, then Apple has a clear responsibility to respond and fix it. So far though, I am finding little credible evidence that this is a true design fault. If you have an individually defective unit, Apple replaces it. If the design is faulty then more needs to be done.

        If there is evidence that the design is faulty (as Johnny Vegas believes) then do something productive and post the evidence.
      • It's an issue because you didn't hear these complaints...

        when the iPad2 was introduced in comparison to the first iPad.

        @use_what_works_4_U The evidence will come when Consumer Reports finishes with their testing, but even their preliminary tests show it can get to 116 degrees Fahrenheit.
      • You Know What?

        A real problem is ignorance. Is it at all clear to people yet that there are many that just can't get past their pathetic bias against Apple? 4 times the pixels! 2.5 times the power consumption! Do you think this gets dissipated by fairies?
      • Please explain

        Let's hear it, explain why it's a problem. Since the Kindle Fire and Transformer Prime run even hotter under the exact same testing are you calling Amazon and Asus full of crap? Are you saying there is a problem with their devices? Oh I get it, it's only a problem because it's an Apple product.
    • How hot?

      But does it reach 116 degrees Fahrenheit? I think there are two heat issues. The overall increase of 10 degrees and the additional instance of the corner area to the left of the home button which points to the heat being dissipated by the GPU.
      • Only 1 report of 116*

        I have only seen on report of that temp but numerous reports stating it to get to the mid to upper 90s. There is a huge difference between those temps and you also neglect to mention in your haste to bash anything Apple that the new iPad come in cooler than some of it's competitors under the exact same testing.
    • BS! It's not overblown at all, it's a huge problem and Apples full of crap

      It is not within their themal specs. They stated those go up to 95 degrees themselves. CR found 116 degrees. 95 is already uncomfortably hot. 116 is outrageous. 95 is already a poor design, I'd say design flaw. 116 means there's probably a manufacturing flaw involved as well. If you have a iPad that's getting uncomfortably hot for resting on a bare thigh you need to take it back and get it replaced before it's too late to get your money back if they won't replace it. Wait and get one once the problems are resolved. A bad one will not have the same resale value and you'll be stuck with the heat problem for a couple years or until it fries something else inside.
      Johnny Vegas
      • We can always count on you

        Mr Vegas to be the voice of ihaters everywhere to help overblow an issue.
      • Apple

        Well when your told what you can do with your product, what you can put on your product, how you use your product do you expect anyone to believe if there is a problem? If one person complains about heat then it's a problem, just because you afraid to wine about your favorite toy doesn't make the problem go away. You would complain about MS if it was them why not apple? Sometimes apples are rotten but does it make all apples bad? Just how you use it!