MacBook 16-inch Fan Noise

Just want to chime in I have the exact same problem.

MacbookPro 16inch 1TB/32GB/5500/8core

When I connect an external monitor the fans ramp up like crazy and the aluminium near the touchbar heats up too. Probably not great for the CPU/GPU when it's that hot. I really hope it can be fixed with a software update since this is nuts.

that's interesting. I went and downloaded the app on my iphone (Decibel X) to measure and I am getting 29-32 with the iphone sitting on the middle of my MBP (clamshell mode). when I start typing it goes up to 48-53. It's telling me it's near whisper to rustling leaves. This is with the 2-4k external displays connected and having Indesign, Acrobat, Affinity Designer, mail, messages, preview, Windows 7 in parallels all running.

Add me to the list. When standalone, with nothing running, idle temps are in the 30s. With my 4K monitor connected, idle temps are in the 60s. I've been wondering to myself the past few days why fans spin up more than usual and this thread confirms my suspicions.

5500m GPU-8GB

64GB RAM

I do not have a noticeable heat problem, BUT it was pointed out to me that when I installed istat that my RHS wattage is lowest when nothing plugged in (.7W) and a little higher (7W) when connected to the dock that has 2-4k displays and much higher (20W) when 1 screen is plugged in directly to the laptop and the laptop is open.

My fans rarely turn on to an audible level no matter the configuration. When I am loading large images, exporting a lot of images, or when using FCPx and it's building previews or exporting.

I am very impressed with the power of this machine. There does seem to be some kind of a bug though as I don't think the wattage should change based up on what is plugged in or whether the screen is opened or closed. It seems it should change based up on it's usage instead. Of course, 4k has many more pixels than the built in screen but that doesn't account why 2-4k's through a dock uses less than 1 4k connected directly.

It does sounds like it is actually a bug that can be fixed via software, I do notice when I close the lid the temperature starts dropping instantly.

It's very easy to replicate the problem so it shouldn't be hard for Apple to see it for themself's.

You have the monitors connected with a dock, that seems to “fix” the problem, but I’m pretty confident that if you connect the monitor directly and use it for 30 minutes or more the machine will get hot and the fans will go crazy. We tried 7 different machines and it always happen, sometimes it takes 30 minutes to an hour and sometimes it happens right away but it always happen. But I heard from different people that using a dock will help resolve this issue, so if it works fine with 2 monitors when connected thru a dock I’m hoping it should work just like that when connected directly, so hopefully a software/driver update will finally fix this issue.

Maybe if you understood what I was saying (obviously not) then you wouldn't have replied. For example, Bootcamped Windows isn't optimized to take advantage of the GPU switching and remains only using the dGPU rather than the integrated graphics which causes the MacBook to heat up and use more energy draining the battery much quicker. No matter which way you try and spin it Windows via Bootamp will never offer the same optimized experience as MacOS.

Basically those thermal problems are on all mac books at least since 2013. There are different sources for heat.

CPU, GPU, battery and USB/thunderbolt connections.

At home I am running continuously a late 2013 (4 core 15 inch Mac Book Pro Catalina (10.15.3)) having two desk fans cooling it down. Without it the CPU would be throttled down on all cores (temperature around 100C) and it would become unusable after a few minutes of running. This does not happening in El Capitan. So here the software may be at fault (maybe different thermal thresholds). With external cooling Catalina runs fast and stable.

The batteries of all my mac books (17 inch late 2008, 15 inch late 2013, 15 inch 2018) were bulging (you feel less play on the touchpad over a few years and more heat on the palm).

This is easy to fix. Just offer laptops which are not ultra thin and make the batteries replaceable so users can replace batteries regularly. It is probably Apple's intention to make laptop unrepairable, not upgradable and super thin that is causing those problems. If I would not depend on XCode and other Mac OS only software I would just dump them. Most competitors produce better hardware for less money.

ipotttatsch wrote:

Just offer laptops which are not ultra thin and make the batteries replaceable so users can replace batteries regularly.

That will never happen; among other things the tech press has been complaining that the last few iterations of the MacBook Pro are too thick and clunky.

Max Tech on YouTube claims to have a solution to this problem. Looks like he even has screengrabs from this discussion in video.

As my machine got returned you lot can test out whether this works/is workable for yourselves.

This has nothing to do with Chrome.

I can easily produce the below with NOTHING running.

Using Intel power gadget shows without external monitor CPU is 43 degress and 61 degrees with external monitor connected.

Yes interesting Video, I did disable Turbo boost with that switcher app before but it doesn't really make any difference for me, I guess because I'm not really doing an CPU intensive tasks all the time. I think it will make a difference if you are seeing higher CPU load and that is contributing to excess heat.

So I get what he is saying about the GPU being more powerful and producing more heat but if I disable GFX switching and leave it in discrete mode then disconnect the monitor it runs cool even when watching video and running graphics apps, so the 5500m gpu can run cool even under load. Nothing really explains why simply connecting a monitor makes it heat up so crazy hot.

And before someone explains to me again for the nth time connecting a 4 or 5k monitor is a such GPU intensive situation that it causes massive heat and GPU power consumption. Well how come a tiny fan-less $120 mini pc with windows 10 can do it without a struggle?

There appears to be a LOT of applicable information is his You Tube Video.

CPU:

Someone earlier had suggested turning off Turbo Boost. Max says if you do that your 16-in still outperforms the best 15-in but the CPU stays cool, so the fans don't spool up, and the Video has some measurements.

His other big trick seems to be rolling your own fan profile, to live with the same amount of heat at the CPU as the 15-in, but lower fan noise.

GPU with External displays:

The only clever idea for the external display was to use an eGPU, already suggested and complained about here.

No explanation of why two external displays seems quieter than one, or why using a dock is quieter than direct connect.