MacMini Cooler Stand

I run Indigo on my MacMini 2018 along with my main computing tasks. Recently I noticed that some CPU cores are hitting 100C (212F) so I decided to do something about it. The MacMini draws "cold" air from the bottom and exhausts the hot air from the back grill as shown by this Apple design image:

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My Mini was already seating on this acrylic stand. I looked on the web for similar cooled stands and the best I could find was this acrylic base in AliExpress. I thought I could try to convert my existing base to something similar. I looked around for quiet fans and settled on the Noctua NF-A14 5V PWM. The main features of this fan aside from being a great brand and very quiet fan is that it's 5V variant (rather than the usual 12v PC fans use) so it can be powered with an USB port and has PWM speed control which means I can regulate it to my liking to minimise noise. To control the fan I used the Noctua NA-FC1 4-Pin PWM Fan Controller (I confirmed it works fine with 5v fans too).

The hardest part was cutting the 5mm acrylic base. I was afraid it will crack but the issue with acrylic is not fragility but heat. I watched some YouTube videos to see how to do it. If you cut too fast the acrylic melts back again as you are cutting it. I placed the acrylic on top of a wood panel and secured it with clamps. I then used my Jigsaw with a metal blade (the more teeth the better) as slow as I could go. Even going slow the blade will get too hot so I used metal cutting lubricant to keep the temperature in check hence why there is liquid in the pictures. All in all it went pretty well, the cut is not perfect but with a bit of sanding it's reasonable good and it's not like I will be looking at this all the time. Finally I drilled the holes for the fan and added 4 rubber feet to keep the MacMini raised and improve air flow.

Probably an overkill but it was a fun project to do on a lazy Sunday.

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Nice. I love stuff like this. Thanks for sharing.

Reminds me of my first Apple II, bought it in 1977 i think. At first I had to load one program at a time from a portable cassette player. Later I was able to add a floppy disk.
Thats when it started running hot. So I cut a round hole in the desk top and mounted an old muffin fan and set the Apple above the hole. Worked great. My first printer
I got was a surplus teletype machine, only printed in upper case and made a hell of a racked. Used it to print proposals for customers, they were very impressed and could
not believe that I had my own computer.

Elwood

[jay (support)]

I too have noticed the 2018 mini gets hot - in fact, I was having relatively frequent kernel panics just after I got it. I believe it was some combination of heat and BridgeOS bugs. My high-tech solution for the heat was:

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Wood blocks to the rescue combined with a nifty utility called Macs Fan Control so you can control the built-in fan speeds based on what you see in terms of the various temp sensors. I think I have the heat issue resolved. I also think Apple finally fixed the BridgeOS issue that a lot of Mac users were experiencing on Macs with the T2 chip.

I do want to replace the wood blocks with something else though, just need to figure out with what. Don't really want to add extra fans (noise), I just need to make sure there's plenty of room below for the air to circulate.

I had several shutdowns with my new mini.

Then it put it into a vertical stand. Since then no problems. No fan needed

Karl


Sent from my iPhone using Tapatalk

The Noctua fan I used is extremely silent but obviously if I pump it all the way I will be able to listen to it. However what I do is to use the PWM controller to turn it up as much as I can without being able to listen to it. Since it's a 140mm fan it can move a lot more air at the same RPM than the MAcMini built-in fan. It can also move the same amount of air at less RPMs. Lower RPM means lower noise. In fact one of the main reasons I did this project was to try to see if I could reduce the times when the MacMini fan goes overdrive and I heard the noise of it. So far I can say it has done that. While it hasn't stopped all instances I would say it's less prevalent. Of course these is very workload dependant so I start doing heavy work then the MacMini fan will eventually go into overdrive. But it's certainly smoothing out the peaks and I see a lot less spikes over 80C.

Ran across this article that might be of interest to the people in this thread.

https://hackaday.io/project/162873-mac- ... g-analysis

This video is useful too. If you want the TLDR summary: MacMini CPUs exceed the device's thermal dissipation and tend to do thermal throttling when CPU is heavy loaded. Replacing the thermal paste might give you a slight improvement depending on the CPU and thermal paste used.