MacBook 16-inch Fan Noise

I strongly recommend everyone posts on this feedback form of Apple.

https://www.apple.com/feedback/macbookpro.html

Let them know what you think about their "amazing" 16 inch MacBook Pro.

[Link Edited by Moderator]

I'm a programmer and i've been using Macs since I was a kid, so don't treat me like an idiot, i'm in the 'Pro' range for a reason, i'm a 'Pro' user, not an average consumer, I know what i'm doing.

So let's get a few things straight:

1. This happens on a clean OS (with latest updates) and with no applications or processes running
2. This happens on a single 27" non 4k 2560 x 1440 monitor (Dell U2715H) connected via USB-C to DisplayPort
3. This did not happen on the less powerful 2017 MacBook Pro 15" under the same conditions above
4. Already did the troubleshooting, reinstalled OS, reset NVRAM and SMC, but once again I repeat points #1-3

New out of the box, no load and no configuration, but sorry, if you need to be a computer technician to solve an issue as basic as this, then it's a rubbish product, not 'user error'. But I couldn't even solve it in the end, as it's clearly a design flaw.

This didn't even happen on the less powerful older model which had a worse thermal design.

[Edited by Moderator]

Let me add a little colour with a few additional observations: one thing that seems to inflame the situation is whether the GPU card is active (rather than integrated GPU). What is quite mad is that having Photoshop open forces the system to use the GPU card - even if there is nothing open in Photoshop.

I just did an A / B comparison to build a set number of 1:1 previews in Lightroom (which is exclusively a CPU task). With Photoshop open (ie the GPU card active), the fans peaked at around 4500 RPM; with Photoshop closed (integrated GPU), the fans peaked at around 3200 RPM. This is a significant difference in noise.

So there are two weird things here:

• Even if the GPU card is not doing anything, having it active causes higher temperatures and fan noise
• Photoshop activates the GPU card whether it needs it or not

Watching the temperatures, I'd say the logic for spinning up the fans is pretty good. The system waited until temperatures hit around 90°C before speeding up the fans, and even then only spun them as fast as was needed to keep temperatures in check.

But the behaviour of the GPU card causing high temperatures, even when doing nothing, seems very odd.

Update on dynamic wallpaper theory

After more testing, it seems like I was wrong. Dynamic wallpaper vs static made no difference. Running the exact same software and conditions:

2017 unit does not go above 2000-2500rpm when connected to external monitor

2019 unit goes above 4000-5000rpm within 1-2 minutes of connecting to external monitor and stays there

Both were using the same external monitor and connector, Dell U2715H.

I will try testing on other screens in a shop later and see if it makes any difference.

Also, Apple genius appointment couldn't work out the issue as well and advised just to return for a refund lol. No hardware issues, but they did acknowledge the issue exists and that it seems users are starting to report the issue. They said it's a very new model and maybe try it out later on. So basically:

• You can try different monitors and connectors to see if there is any difference
• Return for a refund
• Test the unit out in store in a few months to see if this stuff goes away and repurchase

So there is an issue, hopefully there is a fix coming.

When I wrote my first comment on this thread, there was no other online mentions of the issue (the machine was too new, probably).

A quick search today, and the issue seems to be discussed more often, at quick glance, here is another 3 threads with very similar complains/symptoms to what is mentioned here in the discussions:

• https://forums.macrumors.com/threads/macbook-pro-16-inch-fan-noise-in-idle-mode.2211699/page-2
• https://www.reddit.com/r/macbookpro/comments/e5lfmq/macbook_pro_16_fan_noise/
• https://forums.whirlpool.net.au/archive/30ylnyq9

I am waiting for my second replacement, hoping to get anything differently (which feels very unlikely at this point).

The machine is just awesome, if it was not for this noisy fans. Hopefully, Apple will figure it out and do something about it. Otherwise, will return it and wait for the next reliable upgrade

People need to read what users are reporting before they blindly come to the defence of Apple.

Enough with the high load excuses and blaming users. Funny how users are automatically to blame when they try to use their computers as they have always done. So Apple is always without fault and users are always at fault?

As i've repeated several times and as confirmed by other users:

• Ran the test on fresh new machines before restoring anything or configuring anything, so you can't blame any user configuration or software, literally, took a new machine, turned on, went through the setup without any configuration or restoring, hooked up monitor, fans go turbo - So can we quit with blaming user programs, workflows and all that rubbish. You can't get any more factory default.
• Test were ran on basic monitors, just a typical 27" 2440x1440, so stop saying we are overloading these machines. There is no 4k, 5k, 6k, dual, triple, fancy high load setups here. Driving a single basic monitor, fans go turbo. Also, connected via display port not HDMI. Didn't matter what brand of screen btw, I went to a store and hooked up to everything I could, fans go turbo - So can we quit with blaming the monitors
• CPU/GPU were idling, once again, these a factory default machines and haven't even loaded a single program

Issue never happened with the 2017 MacBook Pro or any PC competitor which pack just as much power in a smaller space. So enough with saying this is the laws of physics. If you can't do it, then don't sell the product. And it doesn't take a genius to work out that fans going turbo when the CPU and GPU are idling is a BUG!

Already tried every troubleshooting here, nothing works.

Just wanted to chime in with my own experience. I just had to return a 16" MBP (every spec maxed out except storage) because of fan noise under extremely low load (generally under 5%), which is a shame because the performance of the machine was fantastic. But I can't justify owning a machine where having just a few programs opened when connected to external monitors meant the fans went to max (or nearly max) RPM. Tried an SMC reset and all of the usual things that get recommended, and nothing worked.

It seems silly to compare the performance to my comparatively underpowered 2015 13" MBP, but the exact same tasks performed on the 2015 were just as smooth and didn't elicit any fan noise. An example task I used to compare the two devices was:

• Connect to a single external monitor (1440p, MBP closed and lying flat on desk)
• Open ~10 browser tabs in Firefox, plus one YouTube video in 1440p resolution
• Open any other program (Xcode, Logic Pro X, Final Cut Pro X, etc)

During this task, my 2015 13" was dead silent, but my 2019 16" sounded like it was going to lift off of my desk. I get that the 16" is a lot more powerful, and I love that, but we're talking about pretty low CPU/GPU usage here.

On the other hand, the fan noise didn't get any worse when putting stress on the 16". When launching multiple VMs, opening several programs, and opening a ton of browser tabs/YT videos, the 16" continued to run perfectly (and loudly) but my 13" obviously couldn't handle that much pressure. So I appreciate the power/performance of the 16", but the fan noise/thermals definitely have an issue. I don't want to play russian roulette with such expensive devices, so I'm hopeful there's some sort of acknowledgement from Apple in the near future that warrants buying another machine soon.

As a side note, I also noticed extreme fan noise when downloading absolutely anything. If I downloaded the same 2GB file for both MBPs, the 16" would ramp the fans up very quickly, while my old 13" did not engage its fans at all.

So here are my observations using iStat Menu app on the base 16" model:

1. When idle (after restarting) and without external display connected, total system consumption is approx 15W, Radeon GPU is using 2W (don't know why when only Intel GPU is running).
2. When idle with Radeon switched on (forced by gfxCardStatus app) and no external display connected, total system consumption is 22W and Radeon takes 5W (that is perfectly normal).
3. When idle WITH external display (Dell U2515H with 2560x1400 native res) connected using usb-c -> DisplayPort cable, total system consumption is 37W and Radeon takes 18W!

Therefore fans spin up to 2500-3500 rpm which is very loud in a quiet environment and the top part of laptop above touchbar is very hot. CPU temp is hovering around 65C and GPU also around 65C.

Even my old Late 2013 15" with dedicated nVidia card performs much better in the same scenario.

Closing the lid when connected to the external display makes no difference - Radeon still takes 18-20W of power JUST to display a desktop wallpaper.

I am glad I have an extended warranty so when this piece of crap burns itself down because of this fatal flaw I will be glad to return it.

As some people mentioned above - we all need to report this issue to apple so they escalate it to the ones responsible for this.

My friend with 2018 15" MBP with Radeon 555 has done the same measurement as I did with following results:

1. with just external monitor (laptop lid closed) Radeon took 5W
2. with external monitor and lid opened consumption was 15W for radeon

Closing the lid on 16" with 5300 makes no difference on 5 different monitors I have tested (HDMI, Displayport, USB-C connections).

Considering Radeon 5300 has 7nm chip (much more energy efficient) and is more than 2x faster than 555 just only confirms some nasty bug in drivers for 5300/5500.

One should distinguish two things that one doesn't like on the MBP 16:

1. It's hot and noisy when an external display is connected
2. It's hot and noisy always when I work

The first is a clear issue, that hopefully is a software bug and can be fixed. It's not normal when the GPU consumes 2-3 Watts while driving the built-in display and 20 watts while driving an external display with the same or even less resolution. When a GPU consumes 20 Watts the MBP will be clearly hot and extremely noisy. Even while idling.

The second thing is easier. If one works without connecting an external display and finds the MBP hot and noisy one should chose another model with e.g. less cores. This is completely normal when 8 cores under the full load are so hot. I would even say that the cooling system in the MBP 16 is nearly perfect from the technical point of view, it avoids throttling under the full load and allows all 8 cores to work at 3 GHz over the long period of time. Sure all fans going to 5000RPM but it's the price one has to pay.

Concerning the issue with an external display I hope it will be fixed in the driver soon.

Close dropbox, box, adobe Cloud,... any Aps that synchronizes in the background

Reset the SMC here is the procedure (I was holding for 20 seconds not 7 as they suggest):

1. Shut down your Mac.
2. On your built-in keyboard, press and hold all of the following keys. Your Mac might turn on.

• • Control  on the left side of your keyboard
  • Option (Alt)  on the left side of your keyboard
  • Shift  on the right side of your keyboard

Keep holding all three keys for 7 seconds, then press and hold the power button as well. If your Mac is on, it will turn off as you hold the keys.

Keep holding all four keys for another 7 seconds, then release them.

Wait a few seconds, then press the power button to turn on your Mac.

If you do this and don't notice any significant improvement then get your laptop replaced

as you see on my previous post apps are behaving weirdly on Catalina using unnecessary CPU power, especially Mail, probably Safari as well.

Hope this helps.

Once I wrote about this, but just to remember, guys, if you connect you external display and close the lid, the AMD chip consumption goes down to 6-9 watts what makes everything much nicer. The problem is that I don't believe that the lid + an external display need 10-14 watts more.

I fear that Apple can easily skip the problem because:

1. Driving an external display needs more power
2. MBP does not throttle because we have built in a fantastic cooling system (from the tech point of view it's true)
3. There is a "Pro" mode and under 100% load it's ok to be so hot and loud
4. (My own experience) When I use my MBP disconnected from the TB3 or my ext. display and power supply it's really cool, no noise and it's not hot

-> Apple will just skip the real problem. BUT, there is a real problem, at least in driving an external display.

A few question for anyone in this thread who cares to answer:

1. Is this something that could potentially fixed with a software update?
2. Is the problem occurring with both i7 and i9 machines? Also, is the problem occurring with the 5300M graphics card (the least powerful in the MBP 16" lineup)?
3. Does anyone know if Apple plans to acknowledge the problem and do something about it?

I made some experiments ( i9 2.4Ghz, 5500M 8Gb, 64Gb, 1Tb SSD)

At 10% load

• no monitor: 50C and 1750 RPM
• external monitor: 65C and 2250 RMP

If I heat it up by running some CPU intense program and then go back to <10% load

• no monitor: the fan gradually goes down to 50C within 2 min to reach 1750 RPM (with no external monitor) (it is actually pretty hard to get the fans to run at full speed, it takes about 10 minutes at full load)
  • 0:00 min 5500 RPM
  • 0:30 min 5000
  • 0:45 min 4400
  • 1:00 min 4000
  • 1:15 min 3400
  • 1:30 min 3100
  • 1:45 min 2500
  • 2:00 min 2100
  • 2:15 min 1700
• with an external monitor: it take 2 minutes to cool down to 65C but the fan keeps running
  • 0 min 5500 RPM
  • 1 min 5400
  • 2 min 5200
  • 3 min 5000
  • 4 min 4000
  • 5 min 3500
  • 6 min 3000
  • 7 min 2600
  • 8 min 2300

Note: As a comparison: my MacbookPro 2017 (2.9 Ghz Quad-Core i7, Radeon Pro 560 4Gb, 16Gb, 0.5 Tb) with monitor takes about 2 min to get the fan speed back to the base level.

I think it could be a problem with the firmware: it tries to reach 50C but because of the external monitor it gets stuck at 60. The speed at which the Temperature slows down is pretty much the same in both scenarios, but with the external monitor, the base temperature is higher, and the algorithm seems to expect to reach less than 50C.

This is not acceptable for me, because I am a developer and I have often short CPU bursts compiling or running tests. That keeps the laptop hot and often above 4000 RPM which sounds like a workstation in the 80ies.

But it could be a hardware problem as well -- and because I don't know what it is, I will send it back (since I am still within the 14 days) . Sad decision but for a 4,500 Euro laptop, for me, the risk is too high that it is a hardware problem.