How Hot Is Too Hot?

Discussion in 'MacBook Pro' started by Ronin64, Apr 19, 2013.

  1. Ronin64 macrumors member

    Mar 3, 2012
    I've been playing Portal on my MacBook Pro 2010 and it gets very hot. The cpu stays around 90c with the gpu around 80c. I've read that these temps are normal for gaming, but how hot is to hot? And can these high temps reduce the lifespan of the computer?
    Also does anyone recommend using those cooling pad things?

    Thanks in advance.
  2. GGJstudios macrumors Westmere


    May 16, 2008
    Your temps are normal. If you're not already doing so, use iStat Pro (free) or iStat Menus ($16) to get accurate readings of your temps, fan speeds, etc., rather than relying on your sense of touch or sound. A forum member has posted a copy of iStat Pro that has been "tweaked" to enhance compatibility with Mountain Lion. You can download it here.

    The Intel processors used in Macs are designed to automatically shut down to prevent damage if they truly overheat. CPU Tjmax = 105C (221F), GPU Tjmax = 100C (212F) on i3, i5, i7 processors. (Source: Intel)

    Unless there is a rare defect in a Mac, most temps are well within the normal operating range, considering the workload being put 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.

    It is also quite normal for your Mac to become extremely hot to the touch during intensive operations. The aluminum body transfers heat more effectively than other materials used in computer casings, so you will feel the heat more. This doesn't indicate that it's overheating and will not harm the computer to be hot to the touch.

    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). iMacs have 3 fans with minimum speeds in the 800-1200 range. They will spin faster as needed to keep temps at a safe level.

    If your fans are spinning up without increased heat, try resetting the SMC.
    (PRAM/NVRAM has nothing to do with these issues, so resetting it will not help.)

    The intake and exhaust vents are in the back of the computer near the hinge on all Mac notebooks (except the new MBP with retina display, which has intake vents along the sides at the bottom). The iMac vent is a slot on the back near the top of the computer. Make sure the vents remain unblocked to allow your computer to perform at its best.

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

    For Flash-related issues:
  3. mrsir2009 macrumors 604


    Sep 17, 2009
    Melbourne, Australia
    80-90C is within the normal range for gaming, and being at these temps for periods of time won't fry your Mac - It can get up over 100C before it automatically shuts down due to overheating. When it comes to long term damage (as in, affecting the lifespan of the computer) no one really knows wether the computer running hotter will cause it to die sooner. Reasonable periods of hot temps should be more than fine, however if your Mac is constantly up over 90C for years and years, it's life could be shortened. Again, no one really knows for sure.

    As for cooling pads, it might be worthwhile getting one if you game on your Mac frequently. While the computer probably won't suffer heat damage, reaching high temps can cause the CPU and GPU to "throttle back" to prevent them from getting even hotter. And when doing intensive things like gaming, throttling back will reduce system performance and subsequently cause your games to lag or preform poorly. A cooling pad would reduce overall temps and therefore render it unnecessary for your Mac to throttle, thus keeping performance at an optimum level.

    Good luck! :)
  4. Doward macrumors 6502a

    Feb 21, 2013
    I have to respond, as there is too much false information here to ignore.

    Completely incorrect. Increased heat shortens components' life spans, this is a fact. Higher temperatures cause a range of issues:

    1) Increased temperature causes PCB warpage, as that temperature is not spread across the entire PCB (hot spots)

    2) As a PCB warps due to heat, this increases strain on the solder connections, especially when in a ball grid array, causing logic board failure.

    3) Continued heating and cooling causes thermal stress on all connections, and will eventually damage them. The higher those differences, the more stress (aka the hotter then cooler)

    Running elevated temperatures for long periods of time will cause wear and stress on the PCB. Any EE can tell you this. Technically, ANY period of elevated temperature reduces the lifespan of electronics - in other words, your MBP may have lasted 40 years just idling at the desktop, but playing games and letting the system heat up has reduced that by 0.05%. If you intend to unload the laptop after 3 years, don't worry about it. Want to keep it for 6-7 years? Worry about it.

    Due to the thermal design of the MBP Unibody, you will have limited 'success' with a cooling pad. The only cooling pad design that would work well with the unibody MBP would be a ducted system that draws air front under the hinge of the MBP, and exhausts out one or both sides.

    Most cooling pads on the market are designed for the 'normal' PC laptop - draws air in from the bottom and exhausts out the side of the laptop case.

    A a matter of fact, I'd argue you are making things WORSE in the long run with a cooling pad. Apple's aluminum unibody construction means that heat is radiated somewhat effectively from hot spots into the surrounding aluminum, providing the PCB with a somewhat more uniform heating envelope, helping mitigate those 'hot spots'.

    If you cool the aluminum, then the PCB closest to the aluminum will be colder than the PCB where the CPU/GPU are generating all the heat.

    If you truly want to help cool your MBP while gaming, you have two main options:

    1) Fix the heatsink grease issue, and lap/polish the heatsinks (I've done this on my 17 late 2011 - and i have the 2.5Ghz BTO Core i7!)

    2) Elevate the rear of the laptop by approximately 1-2" The exhaust is directed down between the hinge area and the rear of the laptop. When sitting on a desk, the hot air has a hard time getting away from the exhaust area - elevating the laptop will allow the exhaust air to move away quickly.

    As a data point, playing HOURS of StarCraft II (4-6 hours at a time on some days) gives me CPU temps ~75C. Again, on a 2.5Ghz i7, with heatsinks cleaned, lapped, and arctic silver applied.

    You can use the Arrhenius Equation to determine Mean Time To Failure (MTTF) of most electronics, and notice that TEMPERATURE is a factor.

    Heck, just Google "electronic failure rate vs temperature" if you don't want to believe me.
  5. Queen6 macrumors 604


    Dec 11, 2008
    Land of the Unexpected
    No this is normal behaviour same as my 15" Retina. If you are concerned about temperature and want to reduce it elevation of the rear of the machine helps, as sitting flat on the desk only reflects the heat back to the base of the Mac. You can buy passive aluminium coolers like Rain Designs Mstand or iLap. Most powered coolers are designed for PC notebooks and don't work overly well with Mac`s if at all. One cooler that does work efficiently is the Moshi Zefyr 2, as it`s principle of cooling is specifically designed for Apple portables, by blowing the air horizontally across the base of the computer, however don't expect miracles.

    Link: Moshi Zefyr 2
    A cheap USB fan can achieve the same if strategically placed, not as elegant mind, nor as easy to put in your notebooks case :p but they do help to reduce case temperatures.

    You can use software to override Apple`s own cooling algorithm by manually taking control of fan RPM and setting up power profile presets with SMC Fan Control 2.4, or here with UltraFan which allows you stipulate a preset temperature and the software will automatically raise and lower fan RPM`s to keep the system at the predefined temp, which i personally feel is a far more elegant solution. At the end of the day you want to control your system temperature, not your fan rpm`s. For me SMC is now pretty much redundant with the latest release of UltraFan having manual control of the fans RPM, and subsequently i am starting to uninstall it from my own Mac`s. SMC FC is a great app, however although it`s recently updated, functionality is limited compared to some newer apps, equally SMC Fan Control is rock steady stable and a finished product.

    Strictly speaking Apple`s own cooling algorithm works, albeit at sacrifice of increased temps for quieter operation. This has always been the Apple way and is really nothing detrimental to the system, i have one MBP from 2008 all original barring a recent fan change that has an uptime of over 30K hours. The latest MBP`s need less assistance in remaining cool; for some it`s simply disconcerting the heat generated and transferred to the case, although it`s perfectly normal as the aluminium acts as a heat-sync. i have to deal with elevated ambient temperature so at times a software solution is useful. Apart from the passive cooling the Mstands bring they also offer a very sound ergonomic solution. A passive cooler and UltraFan will maximise the cooling, there is little else you can do short of reducing the ambient temperature or the system load. If I know i am going to push a system i will close all apps that are not essential as this can and does make an impact to system temperature.

    High temperatures in general is not overly harmful to your systems, unless you push to the extremes. What is far more detrimental is thermal stress, where temperatures rapidly cycle by significant margins over a short period of time. Anyone striving for great longevity should look to minimise rapid temperature changes, here UltraFan is your best friend.

    Using a RainDesign Mstand, a Moshi Zefyr 2 and latest version of UltraFan I can reduce temperature by over 20C when transcoding an MKV video file, and that is something worth thinking about;

    • Apple default cooling algorithm 99C - 103C (still on Mstand) fans 4K and escalating :eek:
    • Mstand, Zefyr & UltraFan 79C - 82C fans at 5.8K :cool:

    Recently i have been experimenting with a CoolerMaster Notrepal E1 cooling pad, it has a single very large fan 23CM (9") running at 800 rpm, and most importantly moving a significant 91.25 CFM, this is far more than most other powered coolers i have tried.

    The fan by far takes up the majority of the coolers body, runs slow and quiet. As it`s designed for a PC portable i didn't have any high expectations; the cooler runs quiet as in silent, perfect size for a 15" MBP, has USB expansion, single speed with on/off button and lifts the machine a good couple of inch`s of the desk. I chose my Late 2011 2.4 i7 15" MBP, it`s connected to an external display, runs 24/7 and is generally north of 70C (158F) on any given day. Any software solution only results in the MBP doing a fair impression of a "Turbojet" which we all love to loath, as workloads rise and temperatures increase.

    The important part cooling; well as ever with a Mac a mixed bag, the elevation definitely helps versus being flat on the desk. I have little expectation of any cooler reducing a Mac`s internal temperature significantly, what the Notepal E1 was able to do was systematically reduce fan rpm by a good 1K without any increase in internal temperatures, which is a big step forward. With this cooler and a software solution (UltraFan/SMC Fan Control) it`s possible to have a moderate load and a relatively quiet system, and that counts for a lot. The major downside to the Notepal E1 is the size, it`s clearly designed to be "planted" on the desk. when using the 10 degree angle i use a piece of that rubber you can buy for car dashboards, just to ensure the MBP doesn't slip and slide about, just seems prudent with such an expensive notebook perched on the edge of the desk. The Notepal E1 also unusually blows a stream of cool air out of the front to cool the hands which is well unusual, nevertheless not unpleasant on a hot day.

    I still rate the Moshi Zefyr 2 as the best powered cooler for a Mac portable simply due to it`s continuous horizontal air flow, however the pricing and availability make it a tough choice. 1K reduction in fan speed may not sound that big a deal, however if that keeps the Mac below the "Turbojet' threshold then it`s a worthwhile investment for anyone seeking the quieter life :p

    What i have observed over the years is the best solution for a Mac portable is a combination of software, and powered cooler, on my Late 2011 15" MBP (2.4 i7) running both internal & external display`s i run; Ultrafan set to 66C, AdBlock and it sits on a CoolerMaster NotePal E1 this results in a reasonably cool and quiet system. My Retina is better behaved thermally and i just run UltraFan, AdBlock and it sits on a Rain Design Mstand.

    Note: the CoolerMaster Notepal E1 moves a very considerable volume of air, over 90 cubic feet per minute (CFM) a regular PC cooler moving say 40CFM will have little to no effect on an Apple portable, my recent observations are undertaken in an ambient temperature of 25C to 28C, so you may not need to go all the way to achieve a cool, quiet Mac

    The old adage still applies; it`s easier to keep a system cool, than cool-down an already hot machine. This being said it`s not strictly necessary, equally it`s nice to know that there are options for reducing temperature out there.
  6. swerve147 macrumors 6502a

    Jan 12, 2013
    Playing Half Life 2 Episode 2 at native retina res (2880x1800) and everything set to Medium was like having a portable Rigel in my room!
  7. Doward macrumors 6502a

    Feb 21, 2013
    Currently importing / analyzing a 1080p video in FCPX.

    Temp: 68C
    Fan speed: 2500rpm
    Location - flat on my desk.

    Finally going to assemble the video of "how to permanently fix the MBP running hot syndrome".
  8. fatlardo macrumors 6502


    Mar 15, 2011
    WTF this sheeet is expensive!!

    Moshi Zefyr 2

    But it looks really nice and portable. Anyone else here have a review? Dunno bout dropping so much for something if it doesnt work that well.
  9. swerve147 macrumors 6502a

    Jan 12, 2013
    Before dropping $ on that Zefyr maybe try placing a couple of plastic soda bottle caps underneath the back side of your MBP first. You're bound to get at least a couple of degrees cooler just by allowing air to circulate underneath the bottom.
  10. Ritesh.S macrumors newbie

    Apr 20, 2013
    In the world
    When your computer automatically shuts down, then you know it's too hot!
  11. Queen6 macrumors 604


    Dec 11, 2008
    Land of the Unexpected
    Like I say don't expect miracles, however it will help cool a Mac portable, if you don't need the portability or want the looks a cheap USB fan will do the same with a few blocks of Lego ;) No external cooler is going make significant difference to a portable Mac`s internal temperatures.

    What the Zefyr 2 will do is help keep the fans down some, and stop the case from becoming uncomfortably hot. If you are on the go with a Mac it`s a good bit of kit, folded up takes up little space and built to the same quality level as a Reina Mac. Has three fan speeds, third of which is intrusive and best reserved for extreme load and or conditions.

    Best bet is UltraFan and a couple of large rubber erasers to elevate the rear of your Mac. Set UltraFan to around 66C and you will see reduced temperatures and the fans should not be overly intrusive, of course much depends on your workload. I also use a AViiQ passive cooling stand which is another space saving cooler and works well in tandem with UltraFan. It not only helps with the cooling, also the ergonomics and adds literally no bulk when you travel.
  12. Doward macrumors 6502a

    Feb 21, 2013
    Or... open it up and fix what Apple's manufacturing screwed up - the heatsink machine work is sub par, and there is entirely too much heatsink compound on the dies.

    Uploading a video to youtube demonstrating all of this now.
  13. Queen6 macrumors 604


    Dec 11, 2008
    Land of the Unexpected
    Equally this is not the fix for all, if you are getting good heat transference from the die to the heat sync, swapping out the thermal compound will result in negligible returns, and any error may be disastrous. This should be considered a last resort, rather than a primary fix. The most important factor in troubleshooting high operating temperatures is identifying the root cause, anything less may only compound the issue.
  14. Doward macrumors 6502a

    Feb 21, 2013

    The problem is precisely as you have mentioned - you do NOT get good heat transfer from the die to the heat sink, due to the aforementioned reasons.


    (warning - 40 minute video, linking to the actual heatsink removal)
  15. Queen6, Apr 21, 2013
    Last edited: Apr 21, 2013

    Queen6 macrumors 604


    Dec 11, 2008
    Land of the Unexpected
    And this is not an arbitrary fix for all; you need the right tools and most importantly the right skills, as some have found this out to their rue. The temperatures the OP posted are not unreasonable during gaming. As much as you believe this is the "big fix" there are posts here show that it can be very much a "mixed bag" some have seen good results, others little to nothing. Before encouraging others to rip apart their MBP, you need to be certain of "root cause". If the idle temp is elevated, if temp ramp up is rapid and cooling slow (no load), significant throttling then there may be case to start looking at the cooling system. In general cleaning the fans and heatsync`s will do more good on an older machine. If you have the skill`s, the tech spec`s have at, if not there is a lot more you can do before breaking out the screwdrivers :p

    The OP is questioning high temp when gaming, not anything else, the issues with your system are in isolation not as a whole...
  16. Comeagain? macrumors 68020


    Feb 17, 2011
    Spokane, WA
    Yes, this is correct. And according to your numbers, my computer might last 7 days less over the course of 40 years, if I don't "fix" it. If we're talking about 0.05% over 7 years, that's just over a day.
  17. Doward macrumors 6502a

    Feb 21, 2013
    That was simply an example, not an actual test.

    The truth is, nobody can know the exact lifespan. The closest testing I've seen long term was done by JPL for NASA, and you can estimate via the Arrhenius Equation.

    If you're interested in learning more:

    Increased heat = decreased lifespan.

Share This Page