M1 MBA getting a lot hotter than it used to

[rm5]

I was just rendering some 1080p videos, but had to downscale it to 720p because of the requirements of the site I am uploading them to. The render was of 9x 5-6 minute 1080p videos, downscaled to 720p. The first three (which are all roughly the same length) took 40 seconds, 43 seconds, and 1 minute almost. By the third render, the machine was hot (and thus completed the render 15-20 seconds slower than the first two).

I noticed that the MacBook got REALLY hot and started to thermal throttle. However, back a few months ago even, when rendering consistently like this, I never noticed it getting this hot.

This is really strange and somewhat concerning. I've only had this machine for a year and a half and it's already starting to slow down.

Any advice on how to fix/mitigate this problem?

 

[Apple_Robert]

Were you using a different app than you usually use? Did you check the activity monitor history as well as the memory pressure after the rendering?

 

[rm5]

I was using DaVinci Resolve. It was using only 2.5 GB of RAM during rendering. I checked ASITOP (another resource monitor) during the render as well and saw the power draw drop drastically (from 16 W initially to around 9 W at the end).

 

[Toutou]

If you're seeing noticeable slowdowns caused by thermal throttling on a fanless machine, the only possible reasons could be
a) more stuff running on the machine
b) higher ambient temperature or less airflow around the chassis
c) improperly applied thermal paste (this one is quite improbable and also would manifest itself by the chassis staying cooler, not hotter, because of worse heat transfer)

The hardware itself (CPU, GPU, RAM) does not get slower over time, nor does its efficiency (heat per computation) decrease.

 

[senttoschool]

Normally, you might blame the inside getting dusty because the fan pulls in air. But since it's fanless, it's 100% because your software is different or your ambient temperature is different.

 

[leman]

Where are you located and what’s the ambient temperature? MBA is really sensitive to it since it’s a passively cooled design.

 

[rm5]

I live in New Mexico - dry and very hot during the summer. But my house has centralized air, so it does not get hot in the house. Right now, I'm on vacation in Colorado Springs, where it has been very hot lately. The house I'm staying in is 102 years old and has no air conditioning - though this is somewhat aided by means of portable fans, etc., so I keep the windows open. I have the MBA on a large plastic card table. Back home, I use a regular desk.

The fact that it's been so hot (in the upper 90s) and that the house I'm staying in has no air conditioning - only fans and open windows, THAT could be the problem.

This is making me curious because I'm going to a conference in LA in August - I'm bringing my M1 MBA, and I'm now wondering what sort of problems I'm going to have there.

 

[jdb8167]

I live in New Mexico - dry and very hot during the summer. But my house has centralized air, so it does not get hot in the house. Right now, I'm on vacation in Colorado Springs, where it has been very hot lately. The house I'm staying in is 102 years old and has no air conditioning - though this is somewhat aided by means of portable fans, etc., so I keep the windows open. I have the MBA on a large plastic card table. Back home, I use a regular desk.

The fact that it's been so hot (in the upper 90s) and that the house I'm staying in has no air conditioning - only fans and open windows, THAT could be the problem.

This is making me curious because I'm going to a conference in LA in August - I'm bringing my M1 MBA, and I'm now wondering what sort of problems I'm going to have there.

With that ambient temperature, it's likely that is the problem. Does it cool off at night? It must at least somewhat. I would try it well after the sun goes down and see if the throttling decreases. Or go a cafe or something that has air conditioning and try there.

 

[leman]

That could probably explain the issues Check again when you are back in your conditioned home — if the performance issues disappear, you know what it was.

 

[NT1440]

I live in New Mexico - dry and very hot during the summer. But my house has centralized air, so it does not get hot in the house. Right now, I'm on vacation in Colorado Springs, where it has been very hot lately. The house I'm staying in is 102 years old and has no air conditioning - though this is somewhat aided by means of portable fans, etc., so I keep the windows open. I have the MBA on a large plastic card table. Back home, I use a regular desk.

The fact that it's been so hot (in the upper 90s) and that the house I'm staying in has no air conditioning - only fans and open windows, THAT could be the problem.

This is making me curious because I'm going to a conference in LA in August - I'm bringing my M1 MBA, and I'm now wondering what sort of problems I'm going to have there.

Sounds like heat soak.

 

[rm5]

@NT1440 Trust me, it's not as bad as it might sound...

 

[NT1440]

@NT1440 Trust me, it's not as bad as it might sound...

I don’t think it’s a major problem, the machine is just at a high enough ambient temperature that without a fan it can’t expel the excess heat it’s currently experiencing compared to when you’re at home in the AC.

 

[BanditoB]

In Colorado another thing to consider is altitude. If the altitude is considerably higher than at home in New Mexico, that will also be a factor in cooling efficiency as the thinner air at altitude won’t carry as much heat with it.