MacBook 16-inch Fan Noise

When your fans are running on full blast, what does activity monitor say is the culprit? I’ve tracked down many problems in apps and the OS that I could then recall to Apple with a system snapshot using activity monitor.

In my case and for what I read most of us here, there is no high CPU usage, that is the reason we think it's an issue, because if you are running an app (you are compiling a video for example) and it taking a lot of CPU usage, then it's normal for the fans to run at a high RPM, but in my case I'm just browsing the web, no process in the activity monitor is taking more than 4 or 5% usage and the fans are running at 3000 RPM or more (sometimes all the way to 4500 RPM), this is always when an external monitor is connected, if not the machine works just fine.

I called Apple support for the fans/heating issue and they could hear the fans through the phone. After failed attempts to have it fixed over the phone they scheduled me for an appointment at the Apple store. The store employee connected a second monitor and we watched YouTube for about 10 minutes but the fans didn’t kick in. The space above the Touch Bar got hot enough though. Then he ran the diagnostics to test the fans and temperatures through an iPad that somehow could read my Mac and one of the heat diagnostic tests failed. He then suggested to refund me the price I paid for the MacBook Pro 16 and I gladly accepted, as I purchased It just over 14 days ago. When I asked him he said he never heard about the issue before. I suggest that anyone who has similar issue schedules an appointment at Apple store. When they have enough failed diagnostic test cases they might do something about it. I want to purchase another MacBook pro 16 but for now I’m waiting for the issue to be worked out.

I just returned my i9 and ordered your exact same 2nd configuration. Are you still having fan issues with your 5300 4gb? Does it only happen when a monitor, or two monitors are connected? I was hoping the 5500 was the culprit. If so this i7 5300 is going back. Any insight would be much appreciated!

I bought my third MBP 16 yesterday. The problem with the external monitor was repeated. I tried every possible option. Today I can say with confidence:

1. This is a problem on all MBP 16 (5300 and 5500);

2. Everyone has the same symptoms. When connecting an external monitor, the radeon power consumption increases to 20w. the case under the screen gets Very hot. Fans increase their speed to 4500rpm with minimal system load (watching youtube videos).

3. A closed or open MBP 16 cover does not solve the problem;

4. Resetting NVRAM and SMC does not solve the problem;

5. Completely reinstalling mac os doesn't solve the problem;

6. The problem is observed on all external 4K and 2K monitors;

7. Disabling the True Tone parameter does not solve the problem;

8. The problem is not resolved in the latest version of mac os 10.15.3;

9. The problem is not observed when connecting two external monitors!!! Which tells us that this is a software problem and should be fixed by updating mac os;

10. Technical support does not recognize the problem!

We need to get Apple to listen and start dealing with the problem. Be sure to call Apple tech support and get them to start sorting it out, don't just return the device. Get Apple experts to run all possible tests.

So I said before that I don't have this issue. It is no longer the truth. I just connected my MacBook to external display I got in my job (FULL HD) and the fans went crazy (5200RPM). So I disconnected the display - fans went down to 1800RPM, then I connected the display again and so far it is ok (5 minutes). I don't get it.

Having this same exact issue when connected to an external LG Ultrafine Display. The fans kick on almost immediately and are super loud with nearly nothing open. There is also some really strange lag when dragging windows around on the LG display.

Just updated the OS today. ¯\_(ツ)_/¯

What I found even with no load on the MacBook (i.e. plug in an external display, nothing else) the fans will go up and up. I'll be going to a repair center next week.

Thoroughly convinced there's an issue with the GPU power draw when it's powering more than one screen, regardless of resolution or load.

William Kucharski wrote:

To dispute the notion that this is a model defect that makes the product unusable and find out whether the same issues exist on other platforms that use as similar as possible a GPU.

No you are just an annoying troll who is childishly denying genuine issues many folk have. All you are contributing ironically, is unwanted noise.

When I took my noisy 16" back to Apple that said yup, that's very definitely an issue and it shouldn't behave like that. So maybe you should visit Apple stores and start telling Apple staff they are wrong too.

@alek

That's no fun to have these problems.

My experience along with many many others are showing that your blanket statements is not true for all models. I believe that your's is having problems, but certainly not all of the 16" MBP's are.

My 16" is the upgraded video card with 8GB

Mine is dead silent most of the time and I'm driving dual 4k screens (BenQ). Mine is connected using a single TB3 cable to a dock (TS3+). Could that be why I'm not experiencing the issues because the dock is handling the charging and the power, and driving the multiple displays?

Is it possible that BenQ screens aren't making the request that LG (or other brands) to the GPU/Processor?

Is it possible that the software you are using to measure the heat and fan speeds is causing the problems?

I'm only suggesting these things because if your machine isn't defective (and it may be) then it would be best to figure out the software/hardware combination that might be triggering the machine response.

I have tried using only one monitor and it was fine BUT I've been running them through the dock because it has HDMI. I only have 1 cable of USBC to HDMI. Do you want me to try connecting it directly for a longer period of time?

Are you using the MacBook Pro in clamshell mode? If yes, try to run it while your lid is open, and then check the temperatures and your GPU watt usage, and then I guess that you'll find out that those aren't in the right range.

I also have this issue, only seems to show up when an external monitor is connected through usb c. My cpu and gpu went to almost 100 degrees celcius and suddenly rebooted. It happens multiple times a day. When I remove the external monitor the temp drops to around 40 degrees celcius for both cpu and gpu

I wrote about it yesterday, while using external monitor/s in clamshell mode there is no problem.

The issue begins while you are using the internal display as well, i.e. with the lid open.

That's the case:

The lid is open -> the watt usage of the GPU is rising to 18-20 watt -> the temperatures are rising to 60-celsius degrees in idle state -> doing basic tasks -> the fans start to work hard.

Its an HP E233 connected with a display port to usb c cable. It's not a 4K display. I'm using the app "FANNY" to measure the temp. Activity monitor does not seems to be giving different output when connecting an external display. Sometimes Intellij is using 85% of the gpu and windows server 20% for very short times (split second)