11in i5 or i7?

Discussion in 'MacBook Air' started by adamsium, Jul 30, 2011.

  1. adamsium macrumors newbie

    Jul 23, 2011
    I bought the 2011 MBA 11in, 4/128GB, i5 on Wednesday. I'm now very seriously considering exchanging it for the 256GB i7 version, still in the 11 inch size as this is just perfect for me to take to uni. I've read through many, many threads here regarding excessive heat / fan noise issues with the i7, but it seems that some of those with issues were ultimately happy with their i7.

    So, I'd really appreciate anyone with the i7 (particularly the 11 inch model, since much of what I have seen seems to be in regard to the 13 inch model - but any input would be great) giving their thoughts on the i7 now. I'm also wondering what, if any, effect the i7 may have on battery life.

    The last thing I want to do is to exchange the i5 for the i7 only to be unhappy with the i7.

    Any thoughts / comments / suggestions would be really helpful and very much appreciated.
  2. DeusInvictus7 macrumors 68020

    Aug 13, 2008
    Kitchener, Ontario
    Don't have anything to say about battery life just yet since I haven't done a full battery drain test, but as for the heat, the i7 will be about 5-10ish degrees higher than the i5 under load. Idle and light load it shouldn't be much higher. Shouldn't really come as a surprise though. Right now mine is at 51C, but I'm not doing much right now. I was downloading WoW and watching flash videos, and it went up to about 82C.

    Apparently after a few days it settles down and it cools down a few degrees, so I'll post back after/if that happens.
  3. KPOM macrumors G5

    Oct 23, 2010
    I've been happy with my 11" i7. The fan is pretty quiet. While it does run a little hotter than my Core 2 Duo model did, it never feels uncomfortable. The hottest part is the top left corner of the underside, and only when the processor is running at full speed.

    Here are some benchmarks. There's a noticeable difference:

  4. adamsium thread starter macrumors newbie

    Jul 23, 2011
    Thanks for that. It doesn't come as any surprise that they're going to be at least a bit warmer... as long as they're not too hot and making a lot of noise all the time, I'm happy.

    That they seem to cool down a few degrees after a few days was the impression I was getting from what I had read, too. I've seen suggestions that this could be due to initial indexing or something to do with the thermal paste.

  5. adamsium thread starter macrumors newbie

    Jul 23, 2011
    Yes, these are the sorts of figures I've been seeing in regard to the i5 vs 17 issue. There is quite a difference between the i5 in the 11in and the i7. Most of the time, it's not going to be under much load at all, anyway, and you have to expect some heat when it is under a somewhat heavy load.

    So far, I've not even heard the fan in my i5, except when I held it up near my ear to see if it was running. Even then, it was very quiet.

  6. alecgold macrumors 65816


    Oct 11, 2007
    I'm really curious how that settling works?!

    This is a very useful thread for me. I ordered the same maxed out 11".
    I max out the 13"s processor several times a day and the temperature gets up to 78c or sometimes even 82C.
  7. adamsium thread starter macrumors newbie

    Jul 23, 2011
    Yes, I'm curious to know, too. I actually have no idea if it is the case, it's just an explanation that I've read in a couple of different places, so I mentioned it.

    When the CPU temperature is up at those levels (78/82C), how does this translate in terms of the temperature of the exterior of the device? I mean, does it seem overly warm or hot to touch? Would it be too hot to use on your lap, or is it still quite fine on your lap at those sorts of temperatures?

  8. PaulWog Suspended

    Jun 28, 2011
    Thermal paste has a settling time. Some takes only a few seconds, some takes a few minutes, some takes a few hours, and some can take up to a hundred hours to settle.

    If Apple is using a thermal paste which takes an hour+ to settle, and they haven't run the computer before selling it for that length of time, then the thermal paste will still have a bit of time to settle.

    What "settling" is, for thermal paste, is this: thermal paste is the stuff that's applied in a paper-thin coating between the processor and the cooling device (the copper heat pipes inside). Thermal paste is designed to help transfer heat between the cooling device and the processor, because the two devices won't be perfectly sealed together (there will be air between the two devices touching); so the thermal paste serves as a thermal connector which keeps heat traveling as efficiently as possible. When thermal paste is settling, it still has some time to take shape and hardness to its applied area. With heat over time, thermal paste will settle. This all depends on what the thermal paste is made of though, as some are basically settled instantly without even applying any heat.

    Likely this "settling" that people are describing is just a placebo effect. When I run Starcraft 2, it always spikes up to 95 celcius. But over time it will drop down and hover around 88-91 celcius (usually). That's every time I run the game. And the reason being is that once your processor has been hot enough for long enough, it will throttle itself. That has nothing to do with any form of settling... that will happen over and over again every time you test it out from a cold boot.

    So anyways... there's the possibility that there is some settling. Note that settling sometimes means worse temperatures: You can actually get better temperatures before settling in some scenarios! :p But in most cases (and likely this case), it would mean better temperatures. Whether or not the thermal paste actually does have to settle in the Air is something that hasn't really been proven. And even if it does settle, it has yet to be proven that it really does change the peak temperatures. That said, I'm not denying that it could mean a decent change in temps... but I'm saying that based on what I've seen in my Air, there really hasn't been a difference.
  9. Apple Expert macrumors 65816

    Jan 31, 2010
    The i7 does settle down after a few days, however as does the i5. It's just a fct the i7 is faster, but will prosce more heat. It's about 8% faster over the 1.7 i5. I had both and kept the i5 since it's cooler and havent been able to tell this diffrence speed wise yet.
  10. adamsium thread starter macrumors newbie

    Jul 23, 2011
    Thanks for that, useful to know. I basically knew what the thermal paste is, but I didn't know that it can take some time to 'settle'. So, I guess it's a possible explanation, at least.

    Hmm... So, was your i7 *much* hotter, or just slightly warmer? I mean, was the heat in itself a problem? Have you noticed any significant difference in battery life between the two? I know the figures will be different between the 11in and 13in models, but I'm just wondering what the relative battery life was like... essentially, if there was a significant difference or not (i5 vs i7).

    I'd really like the i7, but I just don't want to do an exchange and end up regretting it.

    In the AnandTech review, Anand seems to recommend the i7 upgrade for the 11in in particular. His benchmarks indicate the i7 to be up to almost 30% faster than the i5 in the 11in. Unfortunately, he doesn't yet have specific results for an 11in i7 (for data on heat, battery life and fan activity).
  11. entatlrg macrumors 68040


    Mar 2, 2009
    Waterloo & Georgian Bay, Canada
    Good question. Apple Expert did you compare the battery life between the two?

    My i7 is boxed up already. I can only comment on the heat. If you push either machine just a little you'll notice the i7 is real warm on the bottom and the palm rest area.

    Not burning or really that uncomfortable if you have jeans on, but the i5 is just warm doing the same tasks, that's what I prefer.

    If you push either machine, for example encoding you wouldn't do it on your lap with shorts.

    I never did notice a speed difference at all
  12. Apple Expert macrumors 65816

    Jan 31, 2010
    The battery seems to be a tad better on i5. Maybe 20-30 minutes better. Of course different tasks will produce different results.
  13. adamsium thread starter macrumors newbie

    Jul 23, 2011
    Okay, so it would seem that even with the i5, then, if I was to push it hard enough, I wouldn't want to have it sitting on my bare legs, anyway. And if the warmths would only be described as 'just warm' for the i5 and 'real warm.... not burning', etc, for the i7, I think I'll be fine. I hope. ;)

    I realise that I probably won't see much, if any, difference in most usage. It's more one of those things I'd like to have there for when I do need it. It can't hurt, as long as it's not going to be more of a drawback because of the heat (or potentially shorter battery life).

    So, entatlrg, would I be correct to interpret what you're saying as basically, while it wasn't a real problem in itself, you'd prefer the machine to be less warm, not so much that it was actually problematically 'hot'? What about the fan noise that some were reporting? Was there any issue there?

    I'd really like to know about the battery, also. So, if you do end up exchanging for the i5, it would be great if you could report back with any findings (even if there is no difference to report). I'd be quite satisfied with a slight decrease in battery life, just as long as it's only slight. Would anybody be able to tell me whether an i7 chip will use more battery power constantly, or will it only use more power when it is actually operating above the capability of the i5... basically, when you really push it beyond the level to which you could push the i5?

  14. adamsium thread starter macrumors newbie

    Jul 23, 2011
    Oh, thanks for that. I posted my other reply before I saw this. That would be quite acceptable to me, really.
  15. SpiffyChee macrumors member

    Jul 22, 2005
    my i7 11" 256ssd has given me no problems. Maybe I'm lucky? but whatever, I love it!
  16. adamsium thread starter macrumors newbie

    Jul 23, 2011
    Well, let's hope that either this is indeed the norm or that I can be lucky, too!
  17. entatlrg macrumors 68040


    Mar 2, 2009
    Waterloo & Georgian Bay, Canada
    Yes, if I'm not noticing a speed difference I would lean towards the cooler machine ... I keep changing my mind ... in the back of my mind from my Windows daze I'm a bit of a spec wh*re too :)

    Now, reading more about the battery life ... if I'm going to average 30 minutes longer each time then I'll stick with the i5.
  18. adamsium thread starter macrumors newbie

    Jul 23, 2011
    Haha... Yes, I'm having much the same experience. I haven't made a final decision, but I'm really leaning toward going for the i7. I'm not too concerned about a slight reduction in battery life. Also, I won't generally be pushing the machine too hard. I know that might be seen as a good reason to not bother with the i7 (and perhaps it is), but at the same time, it means that heat won't generally be a problem and I will have the extra power there when I do need it for something. It seems that anything that is going to cause enough heat to be uncomfortable with the i7 will do much the same with the i5, albeit with slightly less heat. Basically, if it's too hot to have in your lap, it's too hot to have in your lap, regardless of exactly just how hot that may be.

    I am extremely glad I got the MacBook Air, though. This isn't a case of 'buyer's remorse' or anything like that - this is my first mac and I absolutely love this machine - it's just that I think the i7 may serve me a little better overall than the i5, and for a little longer, too, perhaps.
  19. alecgold, Aug 1, 2011
    Last edited: Aug 1, 2011

    alecgold macrumors 65816


    Oct 11, 2007
    I forgot to mention that the 13" is a 2010 model, but I've been using it quite long enough to know it's behavior through and through.
    It gets warm to the touch on the left top corner, above the keyboard. The bottom however only gets warm if it's not standing on a table. When I use it on my knees I tend to be sitting with my legs crossed (e.g. on the floor) and not on my knees in a bus/train.
    I don't think the bottom gets that hot that it will become uncomfortable, certainly as I'm always wearing jeans.
    Since updating to lion some core functions tend the get very busy just at once, apparently without any cause consequently the fans start blowing at 4500-5000rpm. Even with that kind of hard work, it doesn't get hot, just warm.

    To be honest, I expect the 11" 2011 i7 to become a bit warmer (smaller encasing, faster CPU, although the 2.13Ghz C2D has the same 17W power consumption, so based on that figure, the i7 should generate less heath and be a tiny bit more efficient), perhaps bordering on hot, but even with that added heath, I don't see it becoming a problem.

    Thanks for the explanation!
    Could indeed be placebo (that is one strong medicine!!!) but perhaps also a little bit of physics at work :) Both doesn't matter that much.

    The 95C on your MBP seems like a bit high, my old, now deceased MBP 13" max had at first temperatures up to 105C, but after an update it settled to 85C maximum.
    My MBA 2010 13" NEVER gets over 82C, and when it stays at 82C, the fan's get up to ±6000rpm. My wife's MBP 13" max never got to 105, it always stays beneath 83C. So there seems to be some variance between the maximum temperature between MacBooks?!

    The MBA is a wonderful machine indeed, reason I bought the i7 is because I want to use it for a long time and just like memory and a hard disk, I learned to always buy the bigger one. It might be more expensive, but you can't easily ad SSD space and you can't add memory at all.
    The heath is no problem for me, I guess with the .1 update of lion the random MDS-sessions firing up might get less and when I encode video's with any significant length I will have a power cord nearby and I usually leave it on my desk/table because it tends to eat all the CPU power.
    With normal work (mail, safari w/o flash, word, excel etc) I expect it to be cool or even cold.
  20. FieldingMellish Suspended

    Jun 20, 2010
    I'm using an 11 i7 and have gotten cool service from it since introduction day. All my stuff was transferred to it at the Apple store, if that makes any difference. I have never gamed on a computer. Adobe graphics suite is my most intensive processing apps.

    I was kind of forced to go i7 because I was side grading from a 13 just beyond the return date (great Apple store service) and wanted both the biggest drive and an 11 inch, which the store had on hand in an i7.
  21. Roman2K~, Aug 1, 2011
    Last edited: Aug 1, 2011

    Roman2K~ macrumors 6502a

    Mar 11, 2011
    Anandtech have just finished testing the battery life of the 11" i7:

  22. NFS macrumors newbie

    Jul 28, 2011
    Melbourne Australia
    Switched to i5

    I cancelled my i7 and now have an i5 4GB 128GB with Samsung SSD and LED. It's blazing fast, quiet, great battery life and cool. Nuff said.
  23. adamsium thread starter macrumors newbie

    Jul 23, 2011
    That's very interesting to see. I'm still really quite tempted to exchange mine for the i7, especially seeing that. Even if there was a slight decrease in battery life, I really wouldn't be concerned... but no decrease is even better! And from what I'm reading now, it seems like heat and such really isn't an issue, except perhaps in a few cases where it sounds like the machine was quite possibly faulty.

    I actually phoned the Apple Store earlier to see if they had any i7's remaining in stock and was told that they didn't. Can anyone tell me if you are able to do an exchange at any Apple Retail Store, or must it be the store at which you made the original purchase? I'm in Australia, although their policies are likely much the same here as elsewhere.

  24. h00ligan macrumors 68030

    Apr 10, 2003
    A hot desert
    I'm not sure why you got voted down for that, maybe for embedding the image.. but the point is - as I stated before - you are going to have more difference dropping a bar of brightness (by far) than processor.
  25. adnoh macrumors 6502a


    Nov 14, 2010
    Its only worth it if you regularly max out the CPU - like working with big pics or video rendering.

    What do you do that will justify the stronger processor?

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