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Tijer · Jun 13, 2006, 07:20 AM

This is a hypothesis that I would like to help you solve.

I have had my hands on 3 (black) macbooks. One of them assemblied week 20, the second week 21 and the third week 23.

The first macbook had no "moo" from the fans, at around 63-69 degrees C (it's ongoing temperature after one hour+ of iTunes and safari running).

The second macbook had a "moo" from the fans. Still the same temperature 63-69 degrees.

The third macbook had no "moo" from the fans. At the same temperature-span.

The only difference between the 3 macbooks was that the # 2. (the mooing one) have had BootCamp (XP) installed on it. I did not notice the Mooing before I had BootCamp installed, so this is the real offset of the hypothesis:

Hypothesis: "the MacBooks will generally moo more after (once) having installed BootCamp, regardless of being in OS X or XP"

(IF TRUE), possible explanations:
- Installing XP brings on the Fan's at full load for quite a while (some 10-15 minutes) - this might take the grease out of the fans and make them permanently louder.
- Installing BootCamp includes updating the EFI (the system's internal native configuration, not tied to any OS). This update might include changed temperature-controls or any other overall configuration in the EFI that affects the fan or temperature.

What I need to stop messing around with this hypothesis is for some of you guys, who own a Macbook (not pro) and who have already installed XP using BootCamp on it - to tell me whether or not you can hear the mooing at around 67-69 degrees C, in a quiet room (it really needs to be quiet).

PS: It might be a dumb hypothesis, but it's an idea.

powerbook867 · Jun 13, 2006, 07:35 AM

I have a base Macbook w/ 2 gig of ram, no BootCamp and the moo.

icruise · Jun 13, 2006, 07:36 AM

My sister's MacBook also has it and no Boot Camp. I don't see how it could possibly affect it.

Tijer · Jun 13, 2006, 07:38 AM

Dammit, then it's put to the grave. Thx for the time.

snoopy199 · Jun 13, 2006, 07:50 AM

I don't have bootcamp installed on my MB and I did get the moo once - when I was doing some heavy duty photoshop work.

I know a ton has been written about this, but it seems to me, that when the temps get to 64-66c the fans trigger, but they ramp up and down so quickly it sounds like a moo. Its like they're stuck in a loop, if that is the case it should be a simple update to the firmware but as we all know there are no simple fixes

powerbook867 · Jun 13, 2006, 09:49 AM

I think DV000 has hit the mark. It seems to happen when the fan ramps up hard (like when I'm ripping a dvd while doing photoshop work). There is probably going to be a firmware fix to ramp the fan a little slower I would think, but it's not a big deal for me..

Socially Awkward Solo · Jun 13, 2006, 10:17 AM

I had a week 20 MacBook, installed XP on it. No moo.

I replaced it with a week 23 macBook, installed XP, no Moo.

Jerommeke · Jun 13, 2006, 01:40 PM

I had a Macbook with no Boot Camp or any Windows emulation on it, and I got the moo.

I suppose the explanation darth-vader000 gives is more reasonable.

Socially Awkward Solo · Jun 13, 2006, 02:07 PM

A Rom update can fix the problem for sure. Question is why does it only effect SOME macBooks?

photoeditor · Jun 14, 2006, 07:07 PM

Perhaps if there are variations in QA in assembly it might account for the difference. A gloppy job on thermal paste might result in an idle of 65C while a good job might mean 60C. The sloppy job, if 65C is indeed where it came in at, would be sitting right below the critical on-ff point for the thermostat on the fan, meaning that it would be right AT the critical point of 67-68C or so for light word processing and email.

Jake_11 · Jun 15, 2006, 12:23 AM

i have xp on my macbook and it doesn't moo. there was a similar issue with the first imac g5's fans, but mine was fine.

kentuckyfried · Jun 16, 2006, 10:31 PM

What is the "moo?"

flukewurm · Jun 16, 2006, 11:51 PM

the fan revvvving. i was sceptical at just how much a computer could sound like a cow. when i heard mine mooing i was certianly taken back a bit.

ael719 · Jun 17, 2006, 12:27 AM

I don't know how to check my MacBook build date, but your hypothesis may be true in my case. I think, but am not too sure that I may have had the moo before installing bootcamp with XP. When I'm in XP running on battery, it moos hardcore, almost non-stop. But in OSX with the power supply it I've only heard it moo once or twice.

michaelb · Jun 17, 2006, 12:30 AM

I guarantee you city kids have never been to the country - a real moo cow sounds louder than a little MacBook fan!

kentuckyfried · Jun 17, 2006, 12:30 AM

sweet, it makes cow-like sounds?

At least it's not like my old G4 tower. That thing was so loud, it was like a helicopter, and I could never leave it on overnight.

Originally Posted by flukewurm

the fan revvvving. i was sceptical at just how much a computer could sound like a cow. when i heard mine mooing i was certianly taken back a bit.

flukewurm · Jun 17, 2006, 02:44 AM

Originally Posted by michaelb

I guarantee you city kids have never been to the country - a real moo cow sounds louder than a little MacBook fan!

so the dozen or so that are in my back yard dont count? ^_^

yeah. its not loud. but it still sounds like a a cow.