Macbook Air core Shutdown on video

I have a MBA and are experiencing the problems described in this thread.
As a pretty ugly workaround i have a desktop fan in my office directed at the MBA 😉 Works nice actually. When I turn it off it takes about 10-15 minutes to get a core shutdown.

Thanks, maybe I'll try that. It does really seems like it's getting worse and worse. Right now it's morning, not very hot, and the only thing I'm doing is looking at some documents in coverflow in finder. And Bam! suddenly one core shutdown. At least kernel_task didn't go crazy, and the computer is still responsive, but still it seems that these days I cannot do anything without the core shutdown. I'm getting more and more worried about using the MBA. What if it shuts down the core in the middle of something critical -- a presentation, a deadline etc?

Did anyone ever get the problem fixed by Apple? I have followed these discussions, and some people had their logic boards replaced by Apple, but I never saw anybody actually reporting that it solved the problem. I do hope Apple comes up with a solution.

I own a MBA and the core shutdown issue is really effecting the way i use it. I believe that if you use your MBA long enough or hard enough you will experience this problem. Here is a the cool book solution...
http://plasmadesign.wordpress.com/2008/04/02/macbook-air-core-shutdown/

here is another article.

http://paulstamatiou.com/2008/05/11/putting-an-end-to-macbook-air-core-shutdown

in it i noticed this important paragraph.

"However, I have noticed that when using CoolBook the MacBook Air is allowed to get very hot (75+ deg C). Just keep an eye on your temps if you do anything extremely processor intensive. I use smcFanControl. http://www.macupdate.com/info.php/id/23049

Rob Randtoul has the specifics for configuring CoolBook for the MacBook Air. It worked for me."

Good luck everyone.

///////////////////////////////////////////////////

here are the COOL BOOK settings from the plasma design article in case something happens to it.

"Firstly, let’s describe the applications UI as abysmal. There is no getting away from it. Maybe it would make more sense to someone with experience in underclocking but the whole point in a GUI is to assist the uninitiated in achieving their goals without having to resort to technical manuals. Needless to say I had to resort to the manual which is thankfully quite good.

After tinkering with the various parameters and following the advice of others on the forum I settled on the following settings…

When power adaptor is plugged in…

600HMz = 0.9V
800MHz = 0.9V
1200MHz = 0.9V
1400Mhz = 0.9V
1600Mhz = 0.95V

When the MacBook is running on battery…

600MHz = 0.9V
800Mhz = 0.9V
1200Mhz = 0.9V

This lowers the voltage supplied to the CPU by 0.2V. Also of note is the removal of the 1400MHz and 1600MHz setting when running on batteries. This has had the following results…

Before Coolbook

Approx CPU temperature under light load 52C
Approx CPU temperature under heavy load 75C
Fan speed under light load 2500rpm
Fan speed under heavy load 6500rpm
Battery life under light load - 3.35

After Coolbook

Approx CPU temperature under light load 43C
Approx CPU temperature under heavy load 62C
Fan speed under light load 2500rpm
Fan speed under heavy load 4250rpm
Battery life under light load - 4.25

Since installing Coolbook, my MacBook Air has suffered no core shutdowns, it has run significantly cooler to the touch, it is quieter (as a result of the lower fan speeds) and it lasts almost an hour longer than usual when running on battery power. As of yet I have found no downsides and I have not experienced any instability. "

geminiimatt,

Do you use the SuperDrive made for the Air? The one powered by the USB port.
If yes does the load of the optical drive effect your settings or is the regulated, switching power supply able to compensate?

How does the load of the SuperDrive effect the voltages you speak of on the regularly configured Air (before CoolBook) ?

thanks

Message was edited by: barkingmad

I feel like it's somehow getting worse on mine. In the beginning I was watching hulu videos no problem, but now, even in itunes, give it about 5 minutes and I get a core shutdown. It's definitely video related. I can run several CS3 apps at the same time without any issues but try to watch a you tube video and it brings the MBA to its knees. I've read that Apple's aware of the problem - let's hope we get a fix soon.

The same here, yet opposite. Yes, it seems also mine is getting worse. However, I never had any problem watching video, and still don't have. On the other hand, running time machine or simply looking through files in coverflow/quicklook makes one core shut down on my computer. So, I don't think it's specifically video related. It's simply the heat load relative to the ambient temperature. I never had a core shut down in my supercooled, airconditioned office, but often at home without aircon.

I did a little poking around and found this image: http://www.ifixit.com/Guide/images/airlogictop.jpg its from the this article: http://www.ifixit.com/Guide/First-Look/Mac/MacBook-Air

My problem is that i have core shutdowns if i use an external cinema display. I am not having any problems when using the internal display of the MBA.

In the image mentioned above a sensor for temperature measurements is glued between the GPU and the CPU. I am just speculating here, but if the sensor causing the core shutdown indeed is the one glued between the GPU and CPU then it is possible that the sensor thinks that the CPU is to hot even though this is not necessarily the case. The CPU sensor should be in an area just measuring the CPU and not the temperature between the CPU and the GPU.

If this is the case it should be easy to change the threshold for when a core shutdown will happen in the firmware.

simenlf,

Nice work ! Great info !

thanks

Yes, It does get worse as time goes by.

I replaced my logic board about 2 months ago and it's almost not usable with my 24" lcd now. I'm worried if they would not find a fix until the warranty on my MBA expires.

If then, when they finally come up with the fix, I'll have to pay to get the fix. Or, if this problem is going to be fixed only with their second generation, mine will never get fixed.

What were apple's practices on this kind of matters in the past?

seanahn,

I have no first hand experience; but I remember reading two or three cases posted here where Apple was flexible and waved the time limit to provide a repair on warranty after limit was passed.

Probably worth pursuing it as much as possible now so you have a history of "unsuccessful" attempts then perhaps they will be shamed into helping you when the time comes.

Hi, I'm a Japanese, and posting from Japan. This problem is also discussed at Japanese Discussion Board. I brought my MBA to Apple Store Ginza last week, and had a phone call from the staff.
He said that there were two types of core shutdown. One is that the core is shutdown when CPU is overloaded, and the other is that the core is shutdown however no software is opened.
The latter one is fixed by replacement of flex IPD cable, and the former one is still origin unknown, he said.

surgeon1974,

Welcome to the Apple Discussions Forum !

Thank you for this information.

Can we assume you were experiencing core shutdown? Have you determined which type?

If yes was it while using an external display for presentations?

Oyasuminasai (forgive if I use this incorrectly)

Dear surgeon1974-san,

Thanks for the post.

I understand that the target audience for MacBook Air may not play games, but the World of Warcraft game (which is a free, albeit lengthy download) can cause the overheating problem every time. All you need is to get in the game (after logging in, all patches done) and play it for about 15 minutes, especially if you play in full-screen mode. The game will abruptly "stutter" and "lag" and ultimately stop animating altogether except for fits and spurts after it has overheated the CPU.

Until the Coolbook software came out, the solution many people tried is to use special (not well documented) in-game commands to restrict the frame rate of the game to five frames per second. This frame rate is nothing short of awful.

R. Bear Helms,

audience for MacBook Air may not play games

Absolutely no interest in video games. If I ever felt like I had time to play a game it would be chess with a real board and pieces, which I love. Too many other interests to, in my view, waste my time for no return. Some of the most brilliant people I have ever known love and enjoy video games. So. I must admit to being "limited". The "limited" Air is just the machine for someone "limited' such as my self.