Using a small magnet to disable MBP internal display while open.

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Hi,

I have seen several videos online showing how to disable the internal MBP display while using an external display. This is to use MBP in clamshell mode without closing the lid and making sure that has enough cooling air.

I am wondering if this damages the MBP ?
 

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I don't recall seeing any info mentioning that running in clamshell mode was harmful. Thus no need for the magnet idea.

- Nick
 
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And keep magnets well and truly away from your MBP.
 
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But if magnets can damage the MBP, why does apple had placed magnets around the display that will be making contact to the MBP base when closing the lid?

This was the question that I must have asked in the beginning of the discussion.
 
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chas_m

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But if magnets can damage the MBP, why does apple had placed magnets around the display that will be making contact to the MBP base when closing the lid?

This was the question that I must have asked in the beginning of the discussion.


No, actually, it wasn't. I can see the first post in this thread and there's no mention of that question. But I'll answer it anyway.

Apple engineers have carefully designed your machine so that the strength, size and placement of their magnets do no harm. Unless you have comparable design knowledge, your use of magnets is likely to compare to their work as a master miniature figurine maker's work compares to that of a two-year-old with some Legos.

Your idea is not a safe or recommended way to accomplish your goal.
 
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I was wondering..actually I had never given this any thought but... We use to have this big magnet that we ran over hard drives to make sure they were erased. I am not sure if that is the same for SSD's. Could a magnet possibly erase or damage the hard drive if used as the OP suggests???

Lisa
 

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@Iclev, running a magnet over HDD's have the destructive effect because HDD"s use magnetic media and the outside magnet completely scrambles everything in there.

SSDs do not magnetic or spinning media, they are entirely flash based and as such less prone to magnets. But that isn't to say that you can't mess up the SSD's ability to hold data by running a magnet over it enough times, it just isn't a reliable way of ensuring that the SSD has been wiped clean..
 

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But if magnets can damage the MBP, why does apple had placed magnets around the display that will be making contact to the MBP base when closing the lid?

Obviously Apple puts a little bit of thought into how computers are designed…and where the magnet is placed (where it will serve it's function & not cause damage. Apple has been using a magnet on laptops for a long long time (at least since the early 2000's).

And again as I mentioned above. Who said using a MacBook Pro on clamshell mode was bad??

Also…it's really not a problem (if the computer is used with an external display and the MacBook Pro's display is open)…to just leave the display on. Or…just adjust the display brightness all the way down till the display goes dark.

This was the question that I must have asked in the beginning of the discussion.

I think you mean "should have asked".;)

- Nick
 
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As to SSDs or solid state storage, a standard magnet would have no effect - a funny analogy quoted below from HERE - though as a retired radiologist, I would be curious how a flash drive would behave in a powerful MRI machine? ;)

Now, as to the effect of a powerful magnet in contact w/ a laptop on some of the other components of a computer, not sure - as for myself, I would keep magnets away from my computers. Dave :)

Fortunately, most modern storage devices, such as SD and CompactFlash memory cards, are immune to magnetic fields. "There's nothing magnetic in flash memory, so [a magnet] won't do anything," says Bill Frank, executive director of the CompactFlash Association. "A magnet powerful enough to disturb the electrons in flash would be powerful enough to suck the iron out of your blood cells," says Frank.
 
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@Iclev, running a magnet over HDD's have the destructive effect because HDD"s use magnetic media and the outside magnet completely scrambles everything in there.

SSDs do not magnetic or spinning media, they are entirely flash based and as such less prone to magnets. But that isn't to say that you can't mess up the SSD's ability to hold data by running a magnet over it enough times, it just isn't a reliable way of ensuring that the SSD has been wiped clean..

That is what I thought. Thanks for the info!

Lisa
 
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I don't recall seeing any info mentioning that running in clamshell mode was harmful. Thus no need for the magnet idea.

- Nick

The reason for this is for the heat it generates with the clam shell closed. If you have an external monitor and using the internal display more heat is generated and doesn't vent as well as with the lid open.
 

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The reason for this is for the heat it generates with the clam shell closed. If you have an external monitor and using the internal display more heat is generated and doesn't vent as well as with the lid open.

What you mentioned would/could be a theory…if this was a situation new to the "Apple notebook world". The fact is…we've been able to operate Apple laptop/notebook computers in clamshell mode for 10+ years.

The detail you missed in my earlier post was…I haven't read anything official to support that using an Apple notebook computer in clamshell mode as being a problem.

If operating in clamshell mode was a problem…Apple wouldn't have suggested we do it all these years.

Prove to me that operating an Apple notebook computer causes over-heating problems…and then maybe we will have something to discuss.;) Even better. Prove your theory to be true…then write an article about it for MacWorld Magazine…and then you'll be famous as well!:)

But at this point what you said is only a theory. And given that for the past 10 years I cannot remember seeing an article saying clamshell mode is bad for a computer (and Apple basically says it's ok to do it)…I think that I will stick with this information at the moment…that operating in clamshell mode is ok!:)

- Nick
 

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If you are really worried about temperatures in clamshell mode the following "fix" is probably safer than using magnets.

1. With the external monitor connected and powered start the laptop as usual. Both screens will be active.
2. Gradually start closing the laptop screen and it will go dark before the lid is completely closed. I'm a bad judge of distance but there will still be a noticeable gap between the upper and lower lid.

I rarely run in clamshell mode but when I do I tend to take Nick's attitude. If this were an issue by now there would be hard evidence or the thermal sensors would be shutting down laptops worldwide.
 

pigoo3

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If you are really worried about temperatures in clamshell mode the following "fix" is probably safer than using magnets.

1. With the external monitor connected and powered start the laptop as usual. Both screens will be active.
2. Gradually start closing the laptop screen and it will go dark before the lid is completely closed. I'm a bad judge of distance but there will still be a noticeable gap between the upper and lower lid.

Just when you think that you've come up with a possible solution…this guy posts a 2nd thread talking about having an external monitor attached to the MBP (while running on battery power).;)

How to disable Macbook Pro's display with the lid open.

- Nick

p.s. I'm sure you saw the thread already…since you replied to it.:)
 
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Obviously Apple puts a little bit of thought into how computers are designed…and where the magnet is placed (where it will serve it's function & not cause damage. Apple has been using a magnet on laptops for a long long time (at least since the early 2000's).

And again as I mentioned above. Who said using a MacBook Pro on clamshell mode was bad??

Also…it's really not a problem (if the computer is used with an external display and the MacBook Pro's display is open)…to just leave the display on. Or…just adjust the display brightness all the way down till the display goes dark.



I think you mean "should have asked".;)

- Nick

Yes that is what I ment, thanks for pointing this :)
 

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