On a sunny day (Wed, 9 Dec 2020 18:56:04 +0000) it happened Adrian Caspersz
 wrote in :

>Yeah, I know the USP is a small circuit board is cool, but keeping the
>actual thing cool with a small poxy fan, while sticking a HAT on top -
>is calling for a much larger box with a better fan, or buying expensive
>miniature 30mm fans with questionable run time life.


I have been running my Pi 4 since September last year 24/7 in this case:
 https://www.ebay.com/itm/173977365692

First Pi4 Buster, did not even apply any temperature update...
raspi95: /mnt/sda2/security/video # temperature
temp=41.0'C

raspi95: /mnt/sda2/security/video # uname -a
Linux raspi95 4.19.75-v7l+ #1270 SMP Tue Sep 24 18:51:41 BST 2019 armv7l
GNU/Linux

The fan started making noises one day, took it apart
and added some vaseline (a lot) on the bearings, very quitet since.

No space for a HAT in this housing,
and to change the SDcard you have to take the case apart.
Also no WiFi comes out of the metal.
But reliable it is.
What I like about it is that it is closed so no things can get to the PCB and
short it.

My old Pi with HAT in a plastic box without fan is much hotter:
root@raspberrypi:~# show-temp
temp=47.1'C
root@raspberrypi:~# uname -a
Linux raspberrypi 3.6.11+ #371 PREEMPT Thu Feb 7 16:31:35 GMT 2013 armv6l
GNU/Linux
Also on 24/7 since about 2013
Last uptime was 275 days or so.. before I had to move it.
Reliable stuff.

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