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Clamshell Mode - technical question

R

RT2020

macrumors regular
Original poster
Feb 18, 2010
236
0
I'm looking at buying a new macbook air and running it connected up to a LCD and in clamshell mode.

I also use my Macbook Pro in clamshell mode. To keep things cool, I keep a small magnet sitting over the lid sensor (this is located just below the right speaker). This fools the macbook Pro into thinking the lid is closed, when it is really wide open. Thus, I can wake and sleep my laptop normally with it connected to a monitor, but with the lid wide open (excellent air cirulation and heat disipation). I'm surprised very few people know of this trick - I've been doing it for years.

So, my question: Is there is a magnetic lid sensor on the Air like on the Macbook Pro?
 
RT2020 said:
I'm surprised very few people know of this trick - I've been doing it for years.
Click to expand...

I'm surprised you care. When you're in clamshell mode, your computer is not on your lap, so who cares how hot it gets?

It's a machine with heat-dissipation properties governed by engineering and the laws of physics, not a human that gets hot flashes. So long as it's not sitting on a blanket or something, and so long as the ambient air temperature is within the rated range, it'll be just fine.
 
RT2020 said:
I'm looking at buying a new macbook air and running it connected up to a LCD and in clamshell mode.

I also use my Macbook Pro in clamshell mode. To keep things cool, I keep a small magnet sitting over the lid sensor (this is located just below the right speaker). This fools the macbook Pro into thinking the lid is closed, when it is really wide open. Thus, I can wake and sleep my laptop normally with it connected to a monitor, but with the lid wide open (excellent air cirulation and heat disipation). I'm surprised very few people know of this trick - I've been doing it for years.

So, my question: Is there is a magnetic lid sensor on the Air like on the Macbook Pro?
Click to expand...
What you're doing is completely unnecessary. You can leave the lid closed in clamshell mode. Mac portables vent through the back, near the hinge, so there's no impact on venting with the lid closed.
 
I don't know the answer, but I have posted the question here before, with no replies other than the crap those above me posted.

I have searched for the magnet with no luck.







.
 
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There are 2 magnets at least on the display itself, about an inch plus towards the webcam, from top right/left corners. Not sure how you trigger the detection though.
 
Mechinyun said:
I don't know the answer, but I have posted the question here before, with no replies other than the crap those above me posted.

I have searched for the magnet with no luck.
Click to expand...

Thank you :)

To the other know-it-all posters above: the reason I would like to do this is because the laptop runs much hotter when the lid is closed. Heat shortens the lifespan of ALL electronic devices and components. It is the number one reason why components fail.

You know those thousands of Time Capsules that mysteriously fail after only 19 months? It's not a mystery actually. The device has inadequate cooling, causing the power supply located inside the device to burn out http://timecapsuledead.org/

I'm not interested in logic-board failure after 2 years of running my Macbook Air at 75c. Just because some Apple Genius drone tells you it’s not an issue, doesn’t mean he isn’t spewing marketing BS.


So, if anyone can help, that would be appreciated.
 
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I don't like running my MacBooks in clamshell mode either, but I don't use a magnet. There's two methods that proved to be quite useful.

1. I close the lid while booting and open it when Mac OS has finished loading.

2. When the system is already operational I close the lid and thereby sending it to sleep, wake it up and re-open the lid.

Either way, the MacBook screen remains blank.
 
You know those thousands of Time Capsules that mysteriously fail after only 19 months? It's not a mystery actually. The device has inadequate cooling, causing the power supply located inside the device to burn out http://timecapsuledead.org/
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Exactly. The device had inadequate cooling. It's a known problem with the Time Capsules, as well as some older AirPort devices.

It's not a problem with any Apple laptop model. The thousands of people who own them and monitor their CPU temps in realtime using iStat and such would have noticed by now if their laptops had inadequate cooling.
 
interrobang said:
Exactly. The device had inadequate cooling. It's a known problem with the Time Capsules, as well as some older AirPort devices.

It's not a problem with any Apple laptop model. The thousands of people who own them and monitor their CPU temps in realtime using iStat and such would have noticed by now if their laptops had inadequate cooling.
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Right, but logic board failures do happen. When your Macbook is running at 75c while other laptops run at 50c, guess which one is more prone to hardware failure? Cooler is better, you cannot argue against that.

Listen, I'm not talking about having your processor run at 95c for a couple hours, that's not going to damage your computer. I'm talking having your processor at 75c consistently over many months…..that's the real killer. Apple won't tell you this.
 
interrobang said:
I'm surprised you care. When you're in clamshell mode, your computer is not on your lap, so who cares how hot it gets?
Click to expand...

For the same reason people care when a desktop gets hot.

Computers running hot is normal anyway, and unless temp goes over 100C there's nothing to worry about.
 
Alvesang said:
I don't like running my MacBooks in clamshell mode either, but I don't use a magnet. There's two methods that proved to be quite useful.

1. I close the lid while booting and open it when Mac OS has finished loading.

2. When the system is already operational I close the lid and thereby sending it to sleep, wake it up and re-open the lid.

Either way, the MacBook screen remains blank.
Click to expand...

Sounds promising. Using this method, can your computer fall asleep by itself? Can you then simply wake it up by pressing the keyboard?
 
ratzzo said:
For the same reason people care when a desktop gets hot.

Computers running hot is normal anyway, and unless temp goes over 100C there's nothing to worry about.
Click to expand...

Again, I am not talking about having your processor run at 100c for a few hours. Anyone who knows anything about electronics understands that its not going to damage your computer.

However, having the processor at 75c consistently over many months…..that is what will ultimately cause components to fail prematurely.
 
About the magnets, I don’t know if the MBA has them or not, but I saw something that might have been them last weekend while I was flying. The sun was coming into the plane and shining right on the MBA's screen. I noticed what I at first thought was a faint smudge, but then as I looked closer I realized the dimensions were too perfect to be accidental. In the direct sunlight, I could make out two rectangular metal strips on each side of the webcam. I don’t know if these are magnets or some other kind of clip, but they’re definitely there.

As for clamshell mode and heat, I use my MBA in clamshell mode all the time at home when it’s connected to my external monitor. I’ve never had an issue with heat, but, if I’m doing some heavier work I’ll open it up just to be safe. I don’t know if this is actually helping anything, but I want to get as much mileage out of this little machine as possible so I’d rather err on the safe side.
 
So whats the consensus about running a MBP in the clamshell mode then? I heard people say that it is not a good idea even because it's not good for the MBP screen to be exposed to heat like that.
 
jon08 said:
So whats the consensus about running a MBP in the clamshell mode then? I heard people say that it is not a good idea even because it's not good for the MBP screen to be exposed to heat like that.
Click to expand...
There is no problem running in clamshell mode. If there was, Apple wouldn't give instructions on how to do it. It's fine.
 
hfg said:
Apple designed their laptop computers to be used in the "clamshell" mode without any problems.:)

Here is an Apple document detailing how:

http://support.apple.com/kb/HT3131
Click to expand...

The above article (thank you for that!) explains clearly how clamshell mode works. The MBA will use its fans based on information gathered from the various sensors around the chassis and components, regardless of clamshell or open mode. To see this in action, try a widget like iStatPro, which shows you temperatures and fan speed info.
 
I agree with the OP. I also prefer running my White MacBook in Clamshell mode with the lid open, using that trick.

My reasoning is that even if it won't necessarily damage the computer if it's running hotter, but it does make a lot more noise because the fans ramp up more. Which is also a part that wears because it's mechanical (and actually the only remaining moving part in the MBA).

Also I've noticed the LCD gets a lot hotter because there is still an air gap below it even though it's closed. It still tries to blow hot air there and thus heats up the space between the LCD and keyboard. Heat isn't good for LCDs nor for the CCFL tubes that are still in my WhiteBook.

By the way, the air gap at the back in clam shell mode is a lot smaller than the one at the edge between the keyboard and screen when it's open. I think that's why it gets so much hotter, it has more trouble cooling itself.
 
I have done a search here and 3 other apple sites...can anyone link me to a post that talks about his/her MBA blowing up/overheating becasue they used the clamshell mode?

I can't find a single one....
 
glen e said:
I have done a search here and 3 other apple sites...can anyone link me to a post that talks about his/her MBA blowing up/overheating becasue they used the clamshell mode?

I can't find a single one....
Click to expand...

The whole "heat will shorten the life of my [Apple portable]" is one of the biggest myths perpetuated on these forums. It simply does not matter if high heat takes 5 years off of your machine's theoretical lifespan, as the components can last for 50.

Those that continuously fill the forums with stupid statements like "omg it DOES matter" I find have a trend of not knowing what they're talking about when I look at their posting history.
 
miles01110 said:
The whole "heat will shorten the life of my [Apple portable]" is one of the biggest myths perpetuated on these forums. It simply does not matter if high heat takes 5 years off of your machine's theoretical lifespan, as the components can last for 50.

Those that continuously fill the forums with stupid statements like "omg it DOES matter" I find have a trend of not knowing what they're talking about when I look at their posting history.
Click to expand...

agreed and that's my point. I get the same thing on the auto forums I visit with people says if they use 10w-30 instead of 10w-20 their engine will blow up. Yet there has never been a post showing that. It's all just people who think they know better than Apple with too much free time, IMO...My 2nd fav post is the "OMG, my indicator shows 99% charge, is my battery bad?!!!"

Common sense ,people....
 
But don't you find it annoying if the fans are so loud? They are struggling a lot more with the lid closed and you can hear it.

And a fan does not last 50 years when it's constantly being revved high. The bearings will wear out long before that. Nobody said anything would blow up, it's just shortening the lifespan, it's that simple.

Edit: You can also see it with other components that are put under a high temperature strain, such as the infamous Xbox 360 'red ring of death' problem which is caused by the solder balls under the GPU cracking from the constant heating/cooling cycles. The way they fixed that in later revisions was to improve cooling and to use newer GPUs with less thermal output. The MacBook Pro GPU (before the Unibody) and even the iBook before that have had similar issues. Running it hotter will make that kind of issue happen more quickly.
 
You can run a Mac notebook in clamshell mode for many years without any issues whatsoever. You'll be ready for a new computer LONG before a Mac would fail due to heat from operating in clamshell mode, barring any manufacturing defects. Does heat shorten the lifespan? Possibly, but you're not likely to keep your computer long enough to notice, unless you typically keep a computer for 12-15+ years.
 
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