I still use my external cooling pad when I’m running a video encode, because it’s a touch quieter than the MacBook’s fan at its loudest (and with the cooling pad running, the MacBook fan doesn’t have to come on at all). However, when I’m not encoding, I leave the pad off and everything has been running fine.

I’ve also had the opportunity to hear two other MacBook fans in action. The first was from a user that said it had never mooed. He couldn’t hear the fan when it was running at low speeds, where I heard it quite clearly, so it’s quite possible it mooed and he didn’t notice. Its overall acoustics were very similar to mine.

The second was from a user who said it had mooed frequently in 10.4.6 and still sometimes in 10.4.7 — hers was a good deal louder than mine when the fan was spinning up, but about the same when it was actually running. There was a sort of rumbly, motor-y noise associated with the fan spinning up which doesn’t happen with mine. This would have made the mooing a great deal more annoying.

I didn’t spend a great deal of time with either of those systems, just fired up Photo Booth to get the CPU usage up and listen to their fans, so I can’t personally confirm how much or little they mooed, just how their fans sounded in comparison to mine.

I’d be very intrigued to know whether you can reproduce the “moo” at all in 10.4.7 or later. Because essentially it’s the main problem for me. I think I can leave without any problems with a continuous fan noise that gets gradually louder when the machine gets warmer. But this “moo” sound was what was driving me/us insane.

Under normal load, subjectively, it doesn’t seem *much* different, but it seems like there’s generally less heat right above the keyboard and more at the vent, so that the fan is moving more air out of the case at speeds so low I can’t hear it.

With the cooling pad, the behavior under heavy load is about the same — it takes a few seconds more to come up to speed, but the loaded temperature and noise level are about the same. Under normal load, it brings the temperature down a bit — 48-50C — but I’m now wondering if it’s worth the noise.

What’s interesting is that when the temperature does climb into the 70s, the fan ramps its speed up in tiny, perceptible shifts — not turning off and turning on, but moving from a very low (imperceptible unless I really try) speed to a slightly faster/louder speed and up to a G5-like hum at full load. I can’t get the temp up to the 100C range now, so I can’t get it up to the super-loud fan noise I heard just a couple of days ago.

What’s odd is that there’s no mention of MacBook fan changes in the 10.4.7 release notes, and in the forums and blogs I’m not seeing much consensus on whether 10.4.7 changed anything. It’s quite noticeable and backed up by numbers here, but some people are recording events just as well as I am but aren’t seeing any changes.

On the other hand, my temps seem to have been higher than average to start with.

I’m not sure what to conclude from all this. Maybe CoreDuoTemp is inaccurate. Maybe Apple slipped in a silent fix in 10.4.7. Maybe some MacBooks shipped with something tweaky in the power management driver, and the recaching of kexts with the system update has returned them to expected behavior.

I haven’t heard a “moo” since the 10.4.7 update, but I haven’t had time to explicitly try to create one, and the room has to be really quiet for me to hear it on this system (so it pretty much has to be when the kids are gone).

And at this point it doesn’t look like Apple makes a machine that meets those needs.

That seems like a very astute assessment of the situation. I like the machine, but it’s not really suited to everything it’s being marketed for, and there’s a significant part of the iBook niche that sits unfilled in the current lineup.

Since I do computer support, I’m hopeful that I’ll be able to sample other mooing MacBooks at some point. I’ll comment again if I come up with interesting data.

I suppose it is possible that the mooing is not as loud on your machine as it was on ours. It’s something that will be pretty hard to establish, though. But the fact that you are sensitive to noise and that this doesn’t particularly bother you does seem to indicate that it’s not as pronounced on yours—unless you have lots of constant background noise in your room. For the record, in my room with the G5 Quad, I could still notice the mooing. It was obviously not as loud as the G5, but it was still noticeable.

I don’t think I can imagine using a cooler pad on a regular basis in my wife’s situation. I am glad it’s working out OK for you, but my wife doesn’t need to run at 200% CPU for hours—not even for a few minutes, for that matter. So she obviously has significantly different and much simpler needs. And at this point it doesn’t look like Apple makes a machine that meets those needs.

I’ve had my MacBook (1.83) about a week now, and I’ve been watching carefully for signs of any of the widely reported problems — mooing, discoloration, etc.

I prepared for fan and heat issues by buying one of those notebook cooler pads. I got the cheapest generic one I could find on geeks.com (USD $12) — it has three blowers and supposedly puts out less than 22 db — certainly loud enough to notice in a silent room, but much quieter than a G5.

Without the cooler pad, and on a flat surface, the MacBook runs pretty hot. CoreDuoTemp says 80-88 degrees Celsius most of the time. The “mooing” appears to be present, but I think it’s quieter on my system than most — I’m very, very sensitive to fan noise, and I don’t find this one especially annoying. A very quiet fan turns on and off every few seconds, but it’s among the quietest fan noises I’ve ever run across — quieter than the hard drive, for instance.

Even under normal usage, the top left of the computer, and the area around the vent under the screen, get too hot to touch comfortably.

Under load (I frequently keep it at 180-200% CPU usage for hours at a time, running background DVD encodes while multitasking), the temperature goes up to 95-105 degrees, and above 100 degrees Celsius, the fan kicks up to full speed, which is LOUD.

However, with the cooler pad, it doesn’t exceed 70 degrees even under hours of heavy load. The fan comes on only rarely, but more subjectively importantly, the area around the vent and the upper left corner stay quite cool to the touch. Overall, I think it’s quieter this way, because the MacBook’s fan is quite a bit louder than the cooler pad under heavy load.

I’m reasonably happy with this situation, but the fact that I was aware of heat and fan issues and planned for them from the beginning plays into this. If I’d found after the purchase that I’d have to do this, I’d probably be upset about it.

None of the other reported issues appear to affect my MacBook — no sign of discoloration after a week of very heavy use, no sounds or excess heat from the power adapter.

Having now heard the mooing on my notebook, I’m hoping that I get a chance to hear, in person, one of the notebooks that has somebody upset.

My guess is that mine is “normal” — where the fan does in fact start and stop repeatedly, but only in a low-RPM mode where it’s insanely quiet. (This MacBook has a fairly quiet hard drive, but the hard drive noises are more audible than the fan when it’s in this mode. Even my iPod’s hard disk noises are louder.) However, it’s clear that yours (and others) must be making a great deal more noise. Given my historic sensitivity to fan noises, I doubt that this is simply a case where I’m either oblivious or can’t hear it.

If that’s the case, it would partially explain Apple’s “it’s normal” default response.

Anyway, this turned out to be a really long comment, but I thought you might be interested in my findings, particularly as regards the cooler pad as a possible workaround. Now that your MacBook is returned, and given the lousy service you received, I certainly don’t expect that you’ll rush out and buy a MacBook and cooler — and I don’t think it’s right and proper that such a thing should be required. But I’m happy enough to consider the problem solved for myself.

As for the G5, I have had my G5 Quad since November 2005, and I haven’t heard the fan noise change once since then. It stays constant. It’s not as quiet as I would like it to be, but it’s pretty quiet compared to the G4 MDD :).

Alan: It’s always interesting to think about the future, but unfortunately we’ve been hearing great promises for a bit too long IMO. First it was the Pentium-smoking PowerPC. Then it was the national security hazard that was the G4. Then it was the G5 that never happened (on a laptop). And then it was, let’s switch to Intel and everything will be great. Now I am starting to think that maybe IBM could have come up with a decent chip for laptops!

Of course, the sad reality might just be that the machine we are dreaming of (powerful, yet quiet, i.e. not unnecessarily powerful to a point that forces to sacrifice the quietness) cannot exist in today’s industry. But I am also starting to think that the whole computing industry has gone a bit gaga. Why do we need such powerful CPUs? Because the software that everybody uses (Adobe, Microsoft) is so poorly written in the first place! And Mac OS X is starting to get that way too… More and more features, less and less efficiency and compactness.

So we get all this power-hungry software (can you really believe that Word 2004 runs no faster on a G5 Quad than Word 5 did on a Mac SE?) and so we need all these powerful chips to run it. And so we get all these heat/noise issues, and no solution in sight…

Now, don’t get me wrong. There is software out there that is well written and efficient and still does need all the power it can get. Audio/video editing, complex image processing, advanced music making, etc. And I am all for Apple providing powerful machines for such purposes. But the MacBook is supposed to be a low-end machine, something for people for whom the quality of ordinary, daily computing tasks such as word processing or basic digital picture management is much more important than the ability to run ultra-complex software—and people who are not willing to endure constant noise as the price to pay to be able to run such software that they don’t need!

There’s clearly a gap in the product line here, and it looks like Apple has failed to fill it. I don’t know if any other computer manufacturer has a product like this, or if they all in that same race for speed, raw power, etc. I suppose you are right that there might be a market for a site/service that actually provides useful comparisons between various product lines by various manufacturers.

But that’s way beyond my competence—and my entrepreneurial skills :).