Filed under: Hardware, Bad Apple, MacBook
Apple Genius says: Moo'ing normal
If you've been keeping up with MacBook sans-Pro news, you may have heard something about an infamous "moo"-like noise coming from the fan. Basically, the fan goes on and off and on and off and on and off continuously, in a vain attempt to keep the machine cool. Now, I'm no engineer, but it certainly doesn't take one to recognize that this isn't normal behavior. (MacRumors discussion here, video of the fan problem here.)I took my black MacBook to the Genius at the Apple store (Oakbrook, by the way) to get this fixed, and his response? "It's normal. A fan will do what it needs to do to keep the machine cool." Gee, thanks.
As you may remember, I had a similar issue with my MacBook Pro. A new fan unit later, this problem was fixed, which certainly leads me to believe that this isn't normal behavior. (I also showed the problem to a friend of mine who is an engineer, and he confirmed that this isn't normal.) I've called AppleCare (an almost guaranteed better experience, every time) and a repair box is on its way. Sigh.
Anyone else have this problem?
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Reader Comments (Page 1 of 3)
Brendan said 7:05PM on 6-21-2006
This story will moooo its way to digg, and then it will moooo its way to the front page! Who taking bets?
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gslax said 7:09PM on 6-21-2006
vain
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Chris said 7:12PM on 6-21-2006
Yeah, this happens to my macbook as well. Guess I'm not as picky, seems like the fan is just doing its job. I'm impressed that they're sending you a new one easy as that... Let us know how it turns out.
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andy said 7:33PM on 6-21-2006
heat issues, discolouration, whineing, constant fan bursts, just teething trouble in the intel swop i hope and not a sign of dropping standards.
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Laurence Anderson said 7:38PM on 6-21-2006
My MacBook has been nothing but perfect.
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Thayne Miller said 7:42PM on 6-21-2006
it will moo when it gets to a threshold, around 69 degrees C. This is NORMAL behavior, but it's not necessarily GOOD behavior. It was engineered very poorly, but nevertheless, whether intentional or not, this behavior was engineered. Sad thing is, is that this is a typical "unstable" system that is easily fixed by anyone that knows half a bean about filters and electrical engineering. I learned how to compenstate for such a system as this within my first year of EE at the university. If you want to prevent the mooing, either run it hotter than 70 degress, or cooler. Put your macbook on a hard, flat surface and the mooing will stop as the temperature decreases.
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Thayne Miller said 7:44PM on 6-21-2006
oh and I forgot to mention. You will experience the same problem with your new macbook and every other macbook you buy. It's not a defect, it's just poor design. you can replace and replace all year long, but until they come out with a new revision, you're just going to have to get used to the mooing, staining, heat, etc. (and the heat by the way is definitely acceptable.)
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Douglas F Shearer said 7:48PM on 6-21-2006
My MacBook 'moos' occasionally, but not all the time. Surely the fan should run slowly instead of on-off-on-off?
Doesn't bother me at all, just like the occasional processor whining.
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Zombie Flanders said 7:59PM on 6-21-2006
I get the moo when plugged in and doing very little, or when I'm on battery but watching video/flash is running/iSight on and I'm also using another program. It doesn't matter what/how many other programs are open, the combo of flash animation/video + doing anything else seems to do it for me. It gets the MacBook to a steady 67-70 degrees, and the moo is soon to come.
I wish that the fan would run a little longer at the slower speed I think it's trying to run at when it moos (which is distinct from when the fans go full bore for sure). It would run longer, cool things down a bit more, and then stay quiet longer. If it made some sound doing that, I would understand and let it be so. Instead, it hovers around the moo point, and sometimes that is annoying as can be.
I think that if you're playing a video game, you're just going to have to expect the fan to go full speed (which is surprisingly loud for such a small computer). That's cool.
But when you're only slightly taxing the CPU, or maybe using it heavy in spurts--which is any kind of multitasking or flash-infused web surfing* it gets tough.
Just so long as my otherwise-awesome MacBook would stop noticeably acting like those robot toys that hit the wall, reverse, turn, go forward, hit the wall, reverse, turn go forward...
*the way most of us, I think, use their computer
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El Payo said 8:33PM on 6-21-2006
In honor of Clarus, I think you should claim that the noise sounds like a "Moof!"
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Nate Orloff said 8:35PM on 6-21-2006
how many MacBooks do you own? O.o
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ZipperSeven said 8:36PM on 6-21-2006
My MBP has never made noise, but then again, I'm a week 16 who installed the firmware fix out of the box.
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ciprol said 8:38PM on 6-21-2006
This is so stupid! Every MB released to date has this behaviour. The guy will just get another machine with exactly the same behaviour. That moo has hardly killed anyone, see it as a feature!
Be patient and wait for Apple to release a firmware update to alter that behaviour, if Apple engineers finds it to be truly out of spec.
Gees, some people just like to waste resources and jack up more cost to Apple. And it'll all eventually be paid by all of us.
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Conrad Quilty-Harper said 8:43PM on 6-21-2006
LOL, you guys!
http://digg.com/apple/Apple_Says_Mooing_Normal
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sjmills said 8:50PM on 6-21-2006
I was wondering how long it would take for a Clarus comment. Thanks! :)
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Reg said 8:52PM on 6-21-2006
As far as I know, every MacBook does this when the processor temperature reaches around 67°. It's as if the fan controller is programmed to cut in at this threshold, then immediately cuts off when the temperature drops a degree.
But seriously, who thinks up these names... "Moo" to describe a soft fan turning on and off?!
I guarantee you guys have never been to the country, because if you stand next to a cow and it moos, it's somewhat louder than a gentle air current!
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Chris Bell said 9:08PM on 6-21-2006
My MBP has never made a mooing sound. Both fans work fine as well. Personally, I think it's probably a manufacturing problem, not design. If it's a design error that means there is something wrong with my machine cause I don't hear it.
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Chris Bell said 9:13PM on 6-21-2006
"But seriously, who thinks up these names... "Moo" to describe a soft fan turning on and off?!"
Wait a sec. I hear my fans winding up but it doesn't sound like mooing to me. It sounds more to me like the fan is hitting the resonant frequency of the case or the fan assembly for a brief moment. It's not bothersome to me.
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Maf said 9:19PM on 6-21-2006
Early Mac Book Pros with original firmware moo. If you upgrade the firmware the mooing goes away, but the fans will run a lot more than they used to. Really it's a choice between mooing or whirring - take your pick.
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Dinesh Cyanam said 10:02PM on 6-21-2006
This is what I posted on the Apple Discussion Forum:
http://discussions.apple.com/thread.jspa?threadID=520190
"My MacBook mooooos everyday...and as you all have observed, it starts between 68C - 70C. The other thing I observed is that at this temp, the apps that are running freeze very frequently and the beach ball starts spinning. BTW I don't run any resource hungry apps.
Is anyone else observing the freezing of apps at this temp?
And this is exactly what I hear:
http://www.appledefects.com/media/moo.mp3
and and also I installed Windows Vista and when my MacBook heated up, I heard the fans running at full speed continuously for some time and I did observe that the system cooled down. Hope I had a temp. monitor program in Vista"
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