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.Danny

macrumors newbie
Original poster
Jan 6, 2006
16
4
Croatia
Hi guys, on my previous MBP (2012 15") putting a magnet on the left side of the keyboard around the middle activated the hall sensor and clamshell mode was enabled even with the lid open.

On the 2017 I cannot replicate this. I tried moving a magnet all around the edges. On a random iFixit forum post (I can't find anymore) someone mentioned that there are now multiple hall sensors as opposed to just one like before to prevent accidental sleeps better. Anyone know their exact location?

The iFixit teardown of the 2016 shows 4 magnets in the display. 2 small ones near the bottom on the left/right side and 2 longer ones along the top. I tried a bunch of combinations here but can't find "the one" that puts it into clamshell mode since I don't know where the sensors are.

Anyone had any luck with this?

[doublepost=1521195976][/doublepost]

Alright I figured it out (woo!) with the help of this picture:
https://d3nevzfk7ii3be.cloudfront.net/igi/mm2g6UFMIvHU5KW1.huge

The magnets in the display don't perfectly overlap the ones in the case. So they need to be held a bit above the ones in the case in order to hit the sensors.

They also need to be a little stronger. I tried some fridge magnets I had and they didn't activate it. I then tried a couple really small round magnets out of some toy or something that I had lying around since forever and with those it activates.
 
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Am I missing something -- What is "clamshell mode" beyond shutting the display? Does this mean you want to turn off the internal display but use an external? Confused about what you could mean...
 
Am I missing something -- What is "clamshell mode"
Just that, shutting the lid but keeping the laptop going. I'm not sure what the value is in putting it in clamshell mode with lid open in all honesty. Clamshell mode is used when you're running the laptop on a desk with a display, keyboard and mouse (you need an external keyboard/mouse since the lid is closed).
 
Just that, shutting the lid but keeping the laptop going. I'm not sure what the value is in putting it in clamshell mode with lid open in all honesty. Clamshell mode is used when you're running the laptop on a desk with a display, keyboard and mouse (you need an external keyboard/mouse since the lid is closed).

I am confused more now, because this implies that in OSX you either: (1) can't only display on external monitor and turn off the internal, or (2) you can't set the display to turn off?
 
I am confused more now, because this implies that in OSX you either: (1) can't only display on external monitor and turn off the internal, or (2) you can't set the display to turn off?
I'm not sure what you're getting at.

Closing the lid while the laptop is hooked up to an external monitor, keyboard/mouse will cause it go into clamshell mode, instead of sleep.

Here's what Apple has to say: Use your Mac notebook computer in closed-display mode with an external display
 
Right, but what does OP want to do?
That's the odd part, he wants to put it clamshell mode but without closing the lid. I don't get it, and I don't see any value in doing that, perhaps I'm missing an important requirement that he has that would explain the benefit.
 
That's the odd part, he wants to put it clamshell mode but without closing the lid. I don't get it, and I don't see any value in doing that, perhaps I'm missing an important requirement that he has that would explain the benefit.

I have found cooling is much better with the lid open than the lid closed. When I'm at my desk I don't really use the laptop screen as it's positioned behind the main screen, so it's pointless having it on.

The keyboard gets pretty hot, and with the lid closed all that heat gets trapped inside and then the keyboard heats up even more, the display heats up as well etc. You can look at that 16 page drama thread of the guy whose MBP overheats and the glue on his display started melting etc if you want an idea of what too much heat does to components.

To give credit to Apple they did allow for the vents to still work by having a space open below the hinge, even with a closed display. But while this gets the air of the vent out, all the residual heat that goes up through the keyboard doesn't get out that way. And that's the main issue.

I do some CPU intensive things at times. I also put the MBP on a laptop cooler with a big (and quiet) fan which helps a lot too.

And as a final benefit in clamshell mode the internal display doesn't get resources allocated to it so performance is a touch better too. This was very noticeable on the 2012 MBP. Not super noticeable on this one as performance was already good, but I didn't run any benchmarks.

I've been doing this with my 2012 MBP for nearly 6 years now and it runs as well as on the first day I bought it. I'm pretty sure doing this has been a big part of it.
 
I have found cooling is much better with the lid open than the lid closed. When I'm at my desk I don't really use the laptop screen as it's positioned behind the main screen, so it's pointless having it on.

The keyboard gets pretty hot, and with the lid closed all that heat gets trapped inside and then the keyboard heats up even more, the display heats up as well etc. You can look at that 16 page drama thread of the guy whose MBP overheats and the glue on his display started melting etc if you want an idea of what too much heat does to components.

To give credit to Apple they did allow for the vents to still work by having a space open below the hinge, even with a closed display. But while this gets the air of the vent out, all the residual heat that goes up through the keyboard doesn't get out that way. And that's the main issue.

I do some CPU intensive things at times. I also put the MBP on a laptop cooler with a big (and quiet) fan which helps a lot too.

And as a final benefit in clamshell mode the internal display doesn't get resources allocated to it so performance is a touch better too. This was very noticeable on the 2012 MBP. Not super noticeable on this one as performance was already good, but I didn't run any benchmarks.

I've been doing this with my 2012 MBP for nearly 6 years now and it runs as well as on the first day I bought it. I'm pretty sure doing this has been a big part of it.

Hmm, so there's no way in Max OS X to disable the internal display and output to the external? Windows has had the option to output "only to x" for as long as I can remember.
 
There is not. You can lower the brightness all the way, but that doesn't actually turn the internal display off. I think there's some boot flags and such one can do, but to me this is more convenient (albeit less so now that 2 magnets are required instead of 1).

I also remember some apps that did it, but in testing on my 2012 MBP I never found something that actually turned the internal display off in such a way that it doesn't impact performance (which is something clamshell mode has always done).
 
why not turn the brightness all the way down and then mirror the display to your external display?
 
That still resulted in a performance penalty before, I haven't tested with this new MBP though. In any case I just don't want to worry about the internal display showing the exact same pic 100% of the time when it's unused. I had burn in problems on my 2012 (which were fixed by Apple for free--they replaced the display).

Even if burn in wasn't a conern either, I simply want clamshell mode with the screen open but turned off and all graphics memory assigned to the external display, like I've used for many years now. It's slightly less convenient with 2 magnets than with 1, but no matter, it's still not a huge deal (to me). :)
 
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That still resulted in a performance penalty before, I haven't tested with this new MBP though. In any case I just don't want to worry about the internal display showing the exact same pic 100% of the time when it's unused. I had burn in problems on my 2012 (which were fixed by Apple for free--they replaced the display).

Even if burn in wasn't a conern either, I simply want clamshell mode with the screen open but turned off and all graphics memory assigned to the external display, like I've used for many years now. It's slightly less convenient with 2 magnets than with 1, but no matter, it's still not a huge deal (to me). :)

How do you exactly use the two magnets? i was using calmshell on my mbp2011 for past few years, i had run some terminal code and i would just switch on the laptop and close the lid halfway while it was booting and click with the mouse the external display would go on and the built in would be off, it def helps a lot in terms of performance.

Even on the 2018 mbp15" while in calmshell mode it runs at 50 deg with general browsing, video streaming and some other tasks, give or take 10-15C lesser than normal.

Can you tell me exact process of how you use the two magnets to put built in display to sleep and activate calmshell with open lid?

thanks
 
How do you exactly use the two magnets? i was using calmshell on my mbp2011 for past few years, i had run some terminal code and i would just switch on the laptop and close the lid halfway while it was booting and click with the mouse the external display would go on and the built in would be off, it def helps a lot in terms of performance.

Even on the 2018 mbp15" while in calmshell mode it runs at 50 deg with general browsing, video streaming and some other tasks, give or take 10-15C lesser than normal.

Can you tell me exact process of how you use the two magnets to put built in display to sleep and activate calmshell with open lid?

thanks
I would like to know this too. On my 2015 mbp , a single really weak magnet on the middle of the left "vent" will trick it into clamshell mode. With my 2017 MBP , I tried moving both weak and strong magnets around the edges of the keyboard and it didn't activate clamshell mode.
 
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I am confused more now, because this implies that in OSX you either: (1) can't only display on external monitor and turn off the internal, or (2) you can't set the display to turn off?
You don't know macOS cannot do either? Are you a Mac user here?
 
The magnets in the display don't perfectly overlap the ones in the case. So they need to be held a bit above the ones in the case in order to hit the sensors.

They also need to be a little stronger. I tried some fridge magnets I had and they didn't activate it. I then tried a couple really small round magnets out of some toy or something that I had lying around since forever and with those it activates.

Exactly what I was looking for. However, I have tried with a few magents on my 2017, 13 inch Mac and cannot get it right. Will you be kind enough to post a picture of your arrangement? I know this an old post but having searched on google for a solution o this, I dont have any other hope.
 
The magnet method to disable the internal display does work. I have a MacBook Pro (Retina, 13-inch, Mid 2014) with a mirrored external display.

With the mac and external display on, I placed a 0.75" diameter round fridge magnet next to the "caps lock" key (by trial and error; either polarity worked), the internal display was turned off while the external display remained on and the lid of the mac remained opened. However, the keyboard on the mac was also disabled so an external keyboard would be required for this method to work. The benefit of this method, as I understand it, is to increase the speed of the mac and also lower the mac's internal operating temperature.
 
I've observed that the macbook pro remains lot cooler in clamshell mode if I keep the vents upside - pointing towards the ceiling.
The battery temperature remains about 38 c when charging and little cooler when the MBP is fully charged.
If I touch the bottom case by hand, it feels warm but hot by any means.
 
Alright I figured it out (woo!) with the help of this picture:
https://d3nevzfk7ii3be.cloudfront.net/igi/mm2g6UFMIvHU5KW1.huge

The magnets in the display don't perfectly overlap the ones in the case. So they need to be held a bit above the ones in the case in order to hit the sensors.

They also need to be a little stronger. I tried some fridge magnets I had and they didn't activate it. I then tried a couple really small round magnets out of some toy or something that I had lying around since forever and with those it activates.


Yeahh great stuff!
On my MBP Late 2016 nTB, it needs 2 magnets, left and right side just where the tab key is. I used weak fridge magnets, and actually had to hover them some millimeters above the case for it to work - so I just put some carton in between and attached them with a weak tape.

IMG_8242.JPG
 
Here is the position of the magnets on the 15 inch MacBook Pro 2017. They are magnets from an old 2.5 inch hard drive, wrapped in tape. I had to change the screen twice, because it got bluish spots, and one guess (besides pressure marks) is the heat from the clamshell mode, so I prefer to leave it open.
IMG_5915.JPG
 
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