macbook air log.

(part of brett's logjam.)

Entries about my Macbook Air, Vinyamar.

12 April 2008

Underclocking a MacBook Air

Several folks contacted me this morning to let me know about more MacBook Air users who have discovered that underclocking their CPUs keeps the processors cool enough to avoid the core shutdown.

The author suggests an application called ‘Coolbook’ which purports to underclock the laptops CPU by lowering the voltage supplied to the processor and by more agressively throttling the speed of the CPU.

Knowing what the Santa Rosa platform is up to, this now makes a certain amount of sense: Rob underclockspowers the CPU by 20%, and further limits the CPU to 75% of max speed (1.2GHZ) while on battery, which in turn has a dramatic cooling effect while only minimally affecting performance. The cooler CPU avoids the shutdown threshold and therefore the UI is more stable.

It appears to be better to suffer 25% degradation all the time on battery, instead of 50% (or more) some of the time. The OS requires a certain minimum processing threshold, but it’s really the CPU threshold that’s of concern. Underclocking appears to keep the load and temperatures under that threshold.

At least one person who emailed me asked if I thought underclocking is a good idea. I honestly have no clue; I’d like to say no, always stick with the manufacturer’s specs. But in this case those specs suck, and if you can do something about it (and undo the underclocking if anything goes wrong), it may very well be worth it.

For more on the core shutdown issue, please see my MacBook Air Log. I’ll continue to post more information there as it comes in.

11 April 2008

A Boy and His Electronic Toys

I’m tickled pink about all the visitors around this site. Thank you for coming! I’m really happy you’re here; please feel free to drop me a line or twitter me and let me know how it’s going.

I started writing about the computers under my care really for just one reason: so that I would have some record of what I’d done, so I could stop making the same mistakes over and over again.

I don’t know if I’ve accomplished that, exactly, but at least it’s been entertaining watching me try.

Since many of you are new around here, and this is an admittedly quirky personal site, let me point you towards some other computer logs that may interest you:


The following computers are currently in service.

Speaking of which…


These computers have left the building:

You will no doubt notice certain themes in the names.

Each computer has its own category, some with more information than others. Hopefully you’ll find something you like.

Thanks again for visiting!


9 April 2008

The Core Shutdown Feature/Flaw

I'm Running Out Of Pictures Since I Returned The Air Yesterday

The MacBook Air core shutdown issue is a result of the Intel Santa Rosa platform’s aggressive thermal throttling of the MacBook Air’s Merom chips:

The Santa Rosa platform comes with dynamic acceleration technology. It allows single threaded applications to execute faster. When a single threaded application is running the CPU can turn off one of the CPU cores and overclock the active core. In this way the CPU maintains the same Thermal Profile as it would when both cores are active.

So, by design, the Santa Rosa platform will throttle itself to keep the heat down.

I kicked myself for missing this while researching the problem. I should have looked at the CPU specs once I knew the core shutdown was responsible for the performance degradation, but I didn’t. Mea culpa. I was thinking as a consumer, not as an IT professional.

Please note: I do not think this excuses the problem. The UI freezes, stuttering, and slowdowns remain unacceptable. The CPU ruins the user experience, which is a bug. A feature that acts like a bug is a bug.

But it does explain it, and therefore allows us — consumers and Apple alike — to address it.

If the Santa Rosa platform is the problem, which I now believe it is, there are very few options available for MacBook Air owners. Either you live with the performance hits, and hope that it is fixed at a later date, or you don’t.

It boggles the mind when you consider the anecdotal return rate that units who don’t exhibit this problem may actually be defective! There are plenty of MBA users who are gambling that they’ll get one of those in the replacement cycle. But not me.

If anything, finding out that this problem is a design feature/flaw strengthened my decision to get off the Air platform (and increased my nostalgia for the PowerPC chipset, but that’s another story.) I am frustrated that it took so long to identify the root cause, but relieved to know that gambling on another unit isn’t worth it.

Since my case dragged on for several weeks at AppleCare, and therefore attracted a bit of attention from management, I used the opportunity to make a few suggestions to them.

  1. Educate Support: Product specialists need to know about this behavior and be able to explain why it happens, and what benefits it brings (if any). First-tier troubleshooting should be revised to better diagnose real mobo problems.
  2. Educate Consumers: Apple needs to address this issue publicly with a technote to stem the tide of replacements.
  3. Fix it in the OS: You can’t change the chipset, but serious efforts can and should be made to reduce the effects of the core shutdown within the OS and better manage single core mode invocation.

The first two suggestions can reduce agent support costs and reverse logistics expenses, as well as improve customer loyalty. I’ve run customer service organizations before, and I know the band-aids you can apply to make support more effective.

The solution lies in #3, though: fix the damn problem.

Sadly, that’s beyond AppleCare’s ken.


Special thanks to Artifex and Mike Rose for publicizing this problem, Josh Kagan for his insight into the Santa Rosa platform, and everyone on Twitter who’s listened to me gripe about this for the past three weeks.

7 April 2008

From Tragedy To Farce

I spoke with AppleCare this evening to initiate the return of my MacBook Air Vinyamar. As a bonus I received the results of Apple Engineering’s analysis of my core shutdown crash data: the system is behaving as designed.

These past few weeks troubleshooting, reinstalling (twice, over Remote Disk, no less, which I can assure you is not speedy), waiting for replacements, talking with technical support — and dropping a core under load is expected system behavior.

Let that sink in for a minute.

Dropping a core under load is a feature, not a bug.

Therefore, since I’ve gotten so good at it, here’s my guide to shutting down one of your MacBook Air’s cores.

The Unfair Version

  1. Begin with a clean, fresh MacBook Air.
  2. Place it on your bed, a pillow, or lap.
  3. Sign on to your network, and start downloading a nice big movie file from your NAS.
  4. Open Activity Monitor, and make sure the CPU monitor is visible.
  5. Open Safari. Watch a movie trailer or two, and then browse YouTube while waiting for the movie to download.
  6. Play the movie with Quicktime or iTunes. Keep opening tabs in Safari. You won’t need more than 10, especially if they’re AJAX-heavy sites.
  7. Turn on Time Machine and start a backup.
  8. When the video starts stuttering or your UI getting sluggish, check Activity Monitor.

Voila! One of your cores has dropped. You’ve halved your processing speed.

Now, the activities described seem harsh, but they’re really relatively normal for someone futzing about on the internet. File transfers in addition to video seem to speed up a core drop, which presents a problem for anyone using Time Machine.

But there are those who will cry foul entirely because of #2. The Air requires some ventilation, and if you place it on a soft surface (even with the vents unblocked) the computer will heat up quickly.

Okay, fair. Try this one on, then:

The Fair Version

  1. Begin with a clean, fresh MacBook Air.
  2. Place it on a flat desk or marble floor.
  3. Sign on to your network and open Activity Monitor.
  4. Fire up a feature-length movie or two, either over the net or from the local disk.
  5. If you’re feeling adventurous, open XCode and do a little hacking.
  6. Read some documentation on Safari or Preview.
  7. Work for about an hour or so.
  8. Wait for the stuttering video and UI lockups. They’ll come.

Heat speeds up the process, but if you keep the CPU under a certain amount of load (doesn’t need to be pegged) it will eventually shut down one of the cores. After an hour or two of a big H.264 file playing in Quicktime, I could get the Air to drop its core under theoretically ideal conditions — on the marble floor of a cool bathroom.

Now, there are users on the Apple support forums who never experience the core dropping. I’m really happy that they don’t. I don’t know what to say to them, other than that whatever their MacBook Airs have, I wish mine would have caught it.

For me, this just hasn’t been worth it. It doesn’t matter how nice the Air is.

This will likely be the last post in my MacBook Air Log. I will ship the computer back to Apple tomorrow to return it classified not as a defective unit, but instead as buyer’s remorse. So shipping’s on my dime, naturally.

My only remorse is that I wasted so much time with it, wanting it to work one way, with those fancy dual cores, when all the while?

Behaving as designed.

Moving on now.

Use The Twitter, Luke

Immediately after posting yesterday’s decision to abandon the MacBook Air, I let the good folks on Twitter know about it. And, no more than a minute after tweeting, AppleCare called to talk. At 8:30 PM on a Sunday!

What the?

I must ascribe this to awesome coincidence, as at no time did either of us mention Twitter on the call. I’m not as fortunate as Michael Arrington to have attracted the attention of a Comcast VP in Philadelphia from his twittering in San Francisco.

Yet, the response was immediate, and at an awfully odd time. Wouldn’t it be great if companies monitored twitter like they do blogs, and resolve customer problems before they spiral out of control? It’s a nice thought.

But I have no proof, so I must assume coincidence.

Anyway, I had written an email on Friday that was the stated reason for the call, and I talked to the rep briefly about returning the Air, which required another call on Monday to coordinate with the Sales team. I set up a time and went back to my computer.

Where, in turn, I received an invitation to join the TUAW Sunday Night Talkcast to talk about my MacBook Air issues.

Wow, The Twitter is really something!

I accepted, and had an engaging time with the TUAW panel. You can hear the results on TUAW or in iTunes, whenever episode #37 comes out. I’ll be in at about the 10 minute mark.

Hopefully, I don’t sound like too much of a dork. We’ll find out in a few days, I guess!

I wanted to make this point last night, and I’ll make it again here: this is not an issue with Apple’s customer service. Having experience managing customer service teams, I found little fault with the behavior of the AppleCare reps. Most of them strived for resolution on the first call, and were willing to work extremely hard to help me diagnose and resolve the problem. My suspicions that this is a problem beyond their ability to solve would sadly be borne out today, which I’ll describe in the next (and hopefully last) post on this matter.

The point of this post is that you never know what a new technology will bring. If you ask me why I use Twitter, it’s an easy response: so my (non-twittering) friends around the country can see what and how I’m doing.

But the side effects are pretty cool, too.

6 April 2008

The Abandoned Halls of Vinyamar

Macbook Air | Vinyamar

“Thus Turgon lived long in bliss; but Nevrast was desolate, and remained empty of living folk until the ruin of Beleriand.”
J.R.R. Tolkien, The Silmarillion

Like Turgon, my time with Vinyamar has come to an end.

Friday I received a replacement MacBook Air which suffered the same problem as the original. It’s now been nearly a month since I chose the Air to start developing applications again, and for all but a short period of time I’ve been frustrated by it. I want so very much to have repeated the delight of my experiences with my iPod, PowerBook, and iPhone.

But the MacBook Air has simply not lived up to that standard.

The physical machine is very nice. It is beautiful, compact, and a joy to handle. The failures of the internals should not be taken as a condemnation of the class design — far from it. The case is a tremendous success. The computer is a tremendous success.

If only the CPU could keep up with it.

I want, so very much, for the Air to be great. I want to enjoy using it. But I don’t. I work on it for a little while, do a few things with it, and then the machine locks up.

I am sure that future revisions will improve. By the time this machine hits its third generation, the core shutdown problem will be a distant memory. But the flaw in my Vinyamar is here, now, and I need a tool that works now. I can’t wait for them to fix it in six months.

So… I guess I’ll go get a MacBook or a MacBook Pro, instead.

Damnit. I so wanted this one to have a happy ending.

4 April 2008

More MacBook Air Core Shutdown Woes


Vinyamar’s replacement arrived today. I unpacked it and didn’t even bother setting it up past logging into the wireless network and downloading a movie from the NAS. Five minutes later, I’d reproduced the core shutdown issue.

I updated the software, rebooted, and reproduced the issue again. It took a little longer under 10.5.2 than 10.5, but it still happened.

So now I really don’t know what to do.

I called AppleCare, and they had me capture data to send to the engineers. I should hear back early next week, but don’t know what they’re going to say that will actually resolve the issue.

I also spoke with one of the AppleCare managers who talked to me earlier, and he wanted to know what he could do to help. I felt bad, because I know that the key to getting good customer service is to know what you want, and ask for it. But aside from a Macbook Air that works right now, I don’t know what else I want that satisfies me. The MacBook is probably small enough, but lacks the three-finger scroll and incredible design of the Air. The MacBook Pro has the power, but with power comes size.

In my short time with the Air, I came to really like the way it was like a folio I could take with me and tuck into a chair next to me. I didn’t even get to travel with it, but I could see it becoming a constant companion. I would RDC into my windows laptop, and Share Screens with Hithlum, and still have two Spaces left over for working, without any problems.

Well, no problems except, of course, for the random freezes. Those admittedly sucked.

Part of me says: just accept it. It’s not that bad.

But the rest of me says: it is that bad, and don’t settle for something that doesn’t make you happy.

So I put Vinyamar II back into the box this afternoon, and left it alone. I don’t think I even renamed it from the default; it’s probably still “Brett Peters’s MacBook Air,” which always makes me wonder what the correct rule is for possessives for proper names ending in sibilants.

And so I wait. Maybe tomorrow will bring something new.

3 April 2008

Returned To Vendor


I packed up Vinyamar to send her on her long journey back home, in anticipation of the replacement Macbook Air arriving later this week. It’s with some relief that I returned to Hithlum.

I really should stop naming my computers. It makes me irrationally attached to what is essentially a highly advanced screwdriver.

28 March 2008

Overheating MacBook Air CPU


If you find yourself using a Macbook Air and wondering why it’s sometimes fast and sometimes slow, and almost always hot and spinning fans on high, check Activity Monitor. If one of your cores is black, you should call AppleCare.

After working with AppleCare all week, the overheating issue with Vinyamar’s CPU warrants a replacement or return. The core should not shut down, under any circumstances, especially not 10 minutes in to any video that I try to play.

So, back she goes. I’ll give the model another chance.

(Apparently, ‘limp mode’ is not actually a feature of the MBAir. Who knew?)

23 March 2008

Macbook Air Configuration Update

Macbook Air | Vinyamar

Well, my plans for maintaining Vinyamar as a secondary machine lasted all of about an hour.

In my defense, I’m basically an idiot.

I’ve discovered the magic of Screen Sharing, which allows me to easily control Hithlum and manage all the music and movies stored over there. It’s really cool.

However, there are two flaws which I need to discuss with AppleCare tomorrow:

There are plenty of other Air owners who aren’t experiencing this problem. Before I get too caught up in configuring this model, though, let’s make sure that we have a good unit.

17 March 2008

OS X on a Macbook Air

macbookair.png I am happy to announce the arrival of my Macbook Air named Vinyamar.

Vinyamar is named after the capital city of Nevrast in Tolkien’s Middle Earth. “Vinyamar” is Quenya for “New Dwelling.” Built on the western peninsula beneath Mount Taras, Vinyamar was the seat of Turgon’s power before he moved to the Hidden City of Gondolin.

The nomenclature of Vinyamar’s primary network is based upon regions of fantasy novels. Macintoshes are named after lands in J.R.R. Tolkien’s works. Linux machines are named after countries in Guy Gavriel Kay’s novels.

(I have, admittedly, bent the rules slightly here by using the name of a city instead of the name of a region. But it’s my network, I’ll use whichever names I like.)



Vinyamar’s intended purpose is as a coding and work laptop, so Xcode and the iPhone SDK will be required. Graphics work will be light to support application development. It will be used as a business laptop, so some internet and encryption utilities will also be required.

My stated reason for choosing the Macbook Air over the Macbook Pro is that the platform embraces constraints and forces me to focus on certain tasks. Only time will tell if this is the right decision.

System Configuration

OS X is preloaded with nearly every tool that I need, so doesn’t require a lot of configuration to be useful. After working with OS X 10.4 (Tiger) for nearly three years on Hithlum, I’ve picked up a lot of modifications and applications that I “can’t live without,” even though I really can. I addressed the UNIX issues first:

Those are the primary UNIX changes that I felt were absolutely essential. Next, I installed the development environment.

While that was installing, I took care of some remaining OS X preferences.

After the development environment was established, I (cautiously) installed several applications. I debated going entirely stock configuration here, but decided there are some things that are worth it.

Interestingly, there are some great applications that didn’t make the initialcut:


If you are interested to see how Vinyamar performs, I invite you to follow along in her weblog, as future updates will be posted there. (There’s even a separate RSS feed.)

11 March 2008

New Computer Weekend

In a strange display of synchronicity, Merrystar and I both ordered new laptops in the last 24 hours.

While I’ll let you know initial impressions and put up new computer pages next week, Merrystar and I have important decisions to make while we wait.

Namely, what are we going to name them? A quick nomenclature refresher:

Hmmm. Lots of thinking to do here.

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