BigSur is overheating my perfect Macbook

Question

i.stoica Author

Level 1

12 points

BigSur is overheating my perfect Macbook

A1398 macbook pro 15" i7 late 2013

I recently had all improved at a local Apple certified service centre

battery replaced
fans and interior cleaned
thermal paste replaced

I was on Catalina until a few weeks ago, then, according to supported BigSur models page, I was able to upgrade.

The OS is pretty and fancy and all, but it is overheating my laptop beyond imagination.

I've booted from an external disk with Catalina to compare for a few days, it still is cool there, I've also booted an Ubuntu Linux 20.04, the same, it is as cool as before BigSur.

This is an issue reported everywhere on the internet, it is clearly present only when using BigSur.

I've tried all solutions proposed everywhere, SMC reset including (had to open the case for this model)

Nothing works, only not using BigSur. As a mitigation before downgrade, I am using free smcFanControl in full blast mode to keep it cool, maybe it helps others.

Is there any plan for Apple to fix this bug ? It really doesn't do justice for such a perfect computer, probably one of the best Apple has ever created.

Posted on Sep 9, 2021 9:11 PM

Reply

Answer 1

Sep 9, 2021 9:14 PM in response to i.stoica

There is no reason to use a third party app to cool your Mac. The Mac and operating system can manage the computer's temperature. If your Mac is overheating it will shut itself down. If you do have an overheating problem you need to take it to an authorized service center for inspection.

Keep your Mac notebook within acceptable operating temperatures - Apple Support

Reply

Answer 2

i.stoica Author

Level 1

12 points

Sep 9, 2021 9:37 PM in response to BobTheFisherman

I'e analysed using

sudo powermetrics --samplers smc -i1 -n1

In "Full blast mode" when ventilators are at max, my sensors show

**** SMC sensors ****
CPU Thermal level: 50
GPU Thermal level: 50
IO Thermal level: 50
Fan: 5700 rpm
CPU die temperature: 65.95 C
GPU die temperature: 49.00 C

If I leave to "Automatic" - the normal/native behaviour - why does he think GPU and IO are 0 ? and look at those temps

**** SMC sensors ****
CPU Thermal level: 38
GPU Thermal level: 0
IO Thermal level: 0
Fan: 1998 rpm
CPU die temperature: 97.61 C
GPU die temperature: 68.38 C

I am not using it when this happens, only the Terminal app is open, nothing in the background.

The only thing I can see in activity monitor that is strange is WindowServer - it spikes often from 20 to 40 and back

Reply

Answer 3

i.stoica Author

Level 1

12 points

Sep 9, 2021 9:20 PM in response to BobTheFisherman

The reason is that the Big Sur does not start the ventilators properly, not as Catalina.

There is no other way to keep the laptop cool on Big Sur, I have 20 degrees in my apartment, it is on a stand, with ventilators.

Why doesn't it have this same problem on Catalina or the Linux boot drives ?

Reply

Answer 4

i.stoica Author

Level 1

12 points

Sep 14, 2021 6:47 AM in response to i.stoica

Fixed it by disabling Spotlight indexing for everything except Applications to still use it as a fast launcher and added my entire home directory to Privacy tab.

No more overheat, all apps work properly, CPU is fast again.

Reply

Answer 5

Sep 14, 2021 7:13 AM in response to i.stoica

Most likely you'd only have had to wait until Spotlight finished indexing. After a new OS install it's normal that Spotlight takes a while indexing.

Reply

BigSur is overheating my perfect Macbook

Similar questions