Macbook Pro 15" - 2.5ghz runs hotter than 2.3ghz cpu?

Discussion in 'MacBook Pro' started by Mind18, Nov 1, 2011.

  1. Mind18 macrumors newbie

    Joined:
    Jul 11, 2009
    #1
    First, I have to say I absolutely love my new 15" Macbook Pro. I came from a Powerbook G4, which I was still getting by with, so obviously it's a huge improvement. Originally purchased the 2.3 ghz w/ ssd version, but then the spec update happened. Was still within the window of a return, so decided might as well do a switch as the price was the same. Didn't realize the return process (via online) was so easy and straightforward. So kudos to Apple for that.

    Received the new computer, 2.5 ghz w/ ssd, the other day and am happy that I made the switch as it wasn't much trouble at all. However, one thing I noticed is that the computer is a bit louder then the previous 2.3 ghz one I had. Still very silent, but I definitely hear the fan more often. Kind of bummed by that a bit, as with the old one, only noticed the fan on rare occasions and loved how absolutely quiet it was.

    Is it correct to assume that the 2.5ghz chip just runs hotter, so the fan RPMs are higher more often? It's also 1 oz heavier then the other one. I doubt I would have ever noticed the performance upgrade, so almost makes me wish I would have just kept the old one.
     
  2. GGJstudios macrumors Westmere

    GGJstudios

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    May 16, 2008
    #2
    Your computer is fine. The Intel processors used in Macs are designed to automatically shut down to prevent damage if they truly overheat (around 100C/212F - 105C/221F, depending on your processor). iStat Pro will give you accurate readings of your temps, among other things.

    Unless there is a rare defect in your Mac, your temps are well within the normal operating range, considering the workload you're putting on it. Websites with Flash content, games and other multimedia apps will put higher demand on the CPU/GPU, generating more heat. This is normal. If you're constantly putting high demands on your system, such as gaming or other multimedia tasks, expect temps to rise and fans to spin up accordingly. It's just your Mac doing its job to maintain temps within the normal range.

    Your fans are always on when your Mac is on, spinning at a minimum of 2000 rpm (for MBPs) or 1800 rpm (for MBAs, MBs and minis). They will spin faster as needed to keep temps at a safe level. If they're spinning up without increased heat, try resetting the SMC. PRAM/NVRAM has nothing to do with these issues, so resetting it will not help. Also, make sure you don't block the vents, which are located at the rear, near the hinge.

    Learn about the fans in your Mac
    Apple Portables: Operating temperature

    Launch Activity Monitor and change "My Processes" at the top to "All Processes". Then look to see what apps may be placing high demands on your CPU/GPU.
     
  3. Mind18 thread starter macrumors newbie

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    Jul 11, 2009
    #3
    I figured the temps are fine, but still find it weird that the 2.3ghz version I had before, I hardly ever heard the fan. Should have ran istat pro on the previous computer before I returned it. Then I could have compared temperatures vs rpm and see if the cpu was indeed running hotter, or maybe somehow the fans were just quieter.
     
  4. GuitarG20 macrumors 65816

    GuitarG20

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    Jun 3, 2011
    #4
    iStat will also tell you what your fans are running at. With my 2.2 i7, the fans rarely spin faster than the 2k idle unless i am pushing the CPU or using it on a surface that doesn't provide good airflow.
     
  5. Mind18 thread starter macrumors newbie

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    Jul 11, 2009
    #5
    With just light web browsing, my fan seems to run at 2600-2900 rpm, which I can hear and notice.
     
  6. GuitarG20, Nov 1, 2011
    Last edited: Nov 1, 2011

    GuitarG20 macrumors 65816

    GuitarG20

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    Jun 3, 2011
    #6
    0.o that is odd... what are your temps at? and can you post a screenshot from activity monitor?
     
  7. TheRdungeon macrumors 6502

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    Jul 21, 2011
    #7
    Yeah you start to notice the noise around 2500rpm I reckon, that would be quite annoying. I'd say there's something taxing you in the background, what does activity monitor say?
     
  8. dusk007 macrumors 68040

    dusk007

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    Dec 5, 2009
    #8
    When they released the 2.3 it was probably about the same as the 2.5 is now.
    Silicon gets better and the chips get cooler this is why intel will sell a small bump after a while for the same money. Therefore a recent 2.3 will almost definitely be better off than a 2.5. Also heat doesn't climb linear at the top limit it climbs quite a bit. (Turbo is 3.3 vs 3.5 Ghz)
    There is also some variance and you might just have gotten a very cool one first and a hotter one next. Or someone also reported louder fans on one of his Notebooks so maybe it is only louder because the fans don't run as quite at the same speed.
    With low load both chips should run 1.2 or 1.6 Ghz and be almost equally cold.
     
  9. Mind18, Nov 2, 2011
    Last edited: Nov 2, 2011

    Mind18 thread starter macrumors newbie

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    Jul 11, 2009
    #9
    It seems to hover at around 63C-65C for the CPU on low load. I just turned on my computer from sleep and starts at around 40C but it slowly makes its way up. I suppose it's just the variance that dusk007 mentioned, but still a bit frustrating.

    Also there shouldn't be any issues having restored the computer with a time machine backup right? Upon restoring, it mentioned it should only be used for the source computer that made the backup. With only the cpu and gpu changed, figured it was practically the same machine. Read in some threads some people doing a full-os re-install to help with some heat problems.
     

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  10. GuitarG20 macrumors 65816

    GuitarG20

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    Jun 3, 2011
    #10
    with those loads, i am surprised yours is running so hot...

    I would think it would hang between 40-50C, especially since I am running a similar load, but at 47C...

    wait. are you switching your Graphics to integrated only or using the dedicated (which happens when chrome is open)? that makes a huge difference in terms of temp.
     
  11. Mind18, Nov 2, 2011
    Last edited: Nov 2, 2011

    Mind18 thread starter macrumors newbie

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    Jul 11, 2009
    #11
    I just have it set to automatically switch. I have an external monitor hooked up though, which I think I read keeps the dedicated graphics on. I will say today, it does appear to be the same temperature, but the fan rpms are maintaining a lower speed. Last night it was around 2600-2800.

    Anyway, thanks for the responses. It's hard not to be suspicious, considering the previous machine I couldn't even hear a hum in regular use (reminded me how people feel with electric cars) and seeing forums about overheating mbps.
     

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  12. ReanimationN macrumors 6502a

    ReanimationN

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    Sep 7, 2011
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    Australia
    #12
    Your new machine may have poorly applied thermal paste. Quality control on 2011 15" MBPs has been terrible, in my experience.
     
  13. GuitarG20 macrumors 65816

    GuitarG20

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    Jun 3, 2011
    #13
    yes, using the TB port automatically turns on dedicated graphics, because apparently it runs through the AMD card.

    That is probably the reason that your CPU is staying so warm, although honestly I think it's still a little high. I would consider taking it into a Apple Store, if possible, and showing them screenshots proving it is running fairly warm.

    How is your battery life?
     
  14. Quinoky macrumors regular

    Quinoky

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    Sep 18, 2011
    Location:
    Groningen, Netherlands
    #14
    Also, Chrome triggers the dedicated GPU. I use gfxCardStatus on my 2.4GHz i7 MBP to force the integrated GPU only and it stays perfectly cool. Using the dedicated GPU does ramp up temps a bit, although it really never triggers the fans so that I can hear them..
     
  15. GuitarG20 macrumors 65816

    GuitarG20

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    Jun 3, 2011
    #15
    Chrome isn't the only thing that turns on the dedicated card. If i check, these are the programs that would turn on my dedicated card:
    [​IMG]
     
  16. Mind18 thread starter macrumors newbie

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    Jul 11, 2009
    #16
    Yeah that's what I'm worried about. Definitely after checking today, the CPU temp hovers around 65C. Wondering if it's worth trying to purchase another one, just to make one last effort of getting a more "perfect" model. Although I would assume it would be from the same production run, so won't be any different. Can't really have my computer stay overnight at the apple store for a check.

    And haven't checked battery left yet. GuitarG20, what's the specs of your MBP?
     
  17. shardey macrumors 6502a

    shardey

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    Jan 28, 2010
    #17
    I would just have to assume it would run a little bit warmer since the clock speeds are higher, but thats not always the case. Since it is the same architecture it might apply here.

    Try using integrated gpu only and see how much of a difference that plays.
     
  18. Mind18 thread starter macrumors newbie

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    Jul 11, 2009
    #18
    Yeah that is what I thought maybe initially. But at low loads, not sure if that would really come into play. I'm going to try using the integrated gpu later, as that could just be the temp difference I'm seeing.
     
  19. shardey macrumors 6502a

    shardey

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    Jan 28, 2010
    #19
    Running Dreamweaver cs 5, photoshop cs5, safari with pandora playing and mail open, It runs under 50°C on a table.

    Regardless, your laptop is no question running on the hot side. I wouldn't mess with the thermal paste unless you are confident you won't mess anything up and void the warranty. This would be the best solution though.

    EDIT:You mentioned it weighed 1oz heavier, than the early 2011 model?
     
  20. Mind18 thread starter macrumors newbie

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    Jul 11, 2009
    #20
    That's really weird. What MBP do you have? And yeah, an "Early 2011" model purchased from a few weeks ago vs 'Late 2011" was about 1oz heavier. Different processor (2.3ghz i7 vs 2.5ghz i7) and the new AMD Radeon HD 6770M GPU though.
     
  21. shardey macrumors 6502a

    shardey

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    Jan 28, 2010
    #21
    The cpu's went from a 2820qm to a 2860qm which the only difference is clock speeds, so I wouldn't see a weight difference there. As far as the 6770, a 6750 rebadged. I'm wondering if they used a heavier board, bigger heat sinks or anything heat related.

    Also you should give fan control a whirl, as you can set your base speeds up a little to control the heat more.
     
  22. GuitarG20 macrumors 65816

    GuitarG20

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    Jun 3, 2011
    #22
    Early 2011 17" MBP
    Core i7- 2720QM (2.2 GHz)
    8 Gigs ram
    750gig 5400rpm HDD
    HD3000 and 6750m GFx...
     
  23. TheRdungeon macrumors 6502

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    Jul 21, 2011
    #23
    I have a 2.2GHZ with the 1GB 5750 and use smc to run fans at 2400rpm (just under audible) when on power as with the external GPU running when plugged into another screen my temps are around 65c with 3 apps open. I'd say the heat would be largely because of the GPU being on. Also another thing probably unrelated, you mention the noise of the fans but HDDs can also be similar in noise to fans
     
  24. Mind18 thread starter macrumors newbie

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    Jul 11, 2009
    #24
    I have a SSD, which is what I originally attributed to the near silent machine. Also GuitarG20, I would imagine you have cooler idle temps due to have more space inside for airflow?
     
  25. squeakr macrumors 68000

    squeakr

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    Apr 22, 2010
    #25
    My early 2011 with 2.3 I7 runs about 68-70C all day with the fans fluctuating. I am driving an external monitor with the internal display and that adds the heat increase for me, depending it is between 10-15C more than when just running the internal display and all else equal (same programs running).
     

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