Stacking up HP laptops on top of each other disables keyboard and display (EliteBook 840 G10)

[COOPITMARTIN]

Hello,

I would like to know if this is a feature or a bug and what the purpose of this is if it is indeed a feature.

I discovered that if you stack up one HP laptop on top of another, it will disable the keyboard and display of the laptop on top. The laptop on top has to be almost 'exactly' placed on top of the other laptop for this to work - if it is off-centre or the edges don't line up and it's offset a bit, then this.. issue doesn't happen. When you move the top computer a bit up or toward any direction the screen will light up along with the keyboard immediately

I can only assume it is triggered by an NFC tag inside the computer? Why though?
I have only tested this with the HP EliteBook 840 G10 currently.

It took me many hours to figure out what was going on as I was about to send the laptop back because it was doing this behaviour. I tried different power cables, docks etc but only realised what was happening when I took another laptop to prepare, stacked that on top of the other two and the same thing started happening. Then as I moved it in frustration, the screen started working which is when I started to realise what was happening. Odd thing to me is that I couldn't find anything about this behaviour online and talking to other people in our IT dept. no one had ever heard of this behaviour before.

Does someone have an explanation for this behaviour? Is this exclusive to the HP EliteBook 840 G10 models or is this a prevalent feature in most laptops? Is this a HP thing or is this ubiquitous in the industry? Any other info about this that ppl should know?
Thank you ahead of time!

[COOPITMARTIN]

Any update on this? Does anyone know anything about this at all?

[pacman01]

Today i also noticed this when stacking a Fury G8 on top of a Fury G7. I have to roughly line them up to reproduce this lock "feature" of the G8. If i switch the laptops the G7 does not go sleep.

[COOPITMARTIN]

Very interesting...

[LeoEaglecounty · Accepted solution]

found this on a separate website explaining the issue. 

Modern laptop screens have a magnetic sensor on the bezel to detect if the laptop lit is open or closed as opposed to the mechanical switch older models had. This wasn't noticed prior because laptops were thicker, now with the thinner laptops the magnetic sensor of one laptop can trigger the laptop above.

This is also the case for magnetic bracelets like those found on the smart watches and fitness devices.

hope this helps! 

[COOPITMARTIN]

That sounds like it could be it! Thank you for helping reveal this mystery!