MacBook 16-inch Fan Noise

When I connect the external monitor the temperature on the USB-C port goes up by 20 degrees or more so you can't guarantee that the high wattage is not causing any issue (check attached image), right now is on the left side and you can see that is 20 degrees higher than the right one.

With all my previous MacBooks I never disconnected the monitor, but now I usually disconnect it 2 or 3 times a week because I tried to avoid the external monitor when possible but if you are implying than disconnecting the monitor 30/40 times since I got my machine will cause this problem, then we have a bigger issue.

I have a 2013 MacBook Pro that I specifically use with Linux and ALL the ports are still working perfectly fine after more than 7 years, so I don't think that connecting and disconnecting a cable less than 50 times (total) will cause this issue.

I wanted to chime in on this: The OP is the CEO of our company, and I'm the COO. Unfortunately he's been banned for a week, so I wanted to post a follow up and give some additional insight into the issues we're having, as well as a few others.

I, too, use the same 16" MBP that many of our employees are using. Last week, I had to do a full SMC reset, which I've never had to do on any previous MBP or MBAir. I, too, see an increase fan usage when doing simple things, things which previously hadn't caused any excessive fan usage. For example, simply starting up a Parallels Desktop VPN spins the fans to over 5500rpm.

Today, I had an employee encounter this:

I've had it too, as have a couple of others who we purchased the new MBPs for. Seems to happen with greater frequency as well, even after the latest update. Again, never had that happen on older MBPs or on the MBAir I used a few years ago.

We've been able to at least circumvent issues by using eGPUs, but adding an additional $600+ to a machine that already runs over $3000 seems a bit excessive. And since we've all moved to a work-from-home scenario we're in video conferences all day. I have to use headphones because the fan noise makes it impossible to talk to others in the conference without them.

[Edited by Moderator]

Just stumbled upon this on Reddit. If it's not allowed then please feel free to remove it. This member has a 16" MBP and two external monitors connected (and he's not using clamshell mode) to it without issue. Interesting timing because he was asked about fan noise with 2 monitors connected. He stated that he has no issue with fan noise under MacOS. As normal he would expect fan noise under Bootcamp'd Windows but he doesn't run Windows. https://www.reddit.com/r/mac/comments/g5f8f8/my_we_can_all_peacefully_coexist_setup/

We had another interesting thing occur today that's similar to that display issue I posted about, but this time it's just when using Chrome browser. I don't believe this is necessarily graphics card related as it happened while we were in a video chat, and she shared her screen with us to show us -- that's how I got the screenshot. EDIT: It's not the first time this employee has seen this, but this is the most recent time it occurred.

This is the ribbon on Office 365:

Has anyone seen anything like this, or have any idea why this would happen in a browser? It's fully updated to the most recent public version. Are there any other Topics anyone knows about with an issue like this? Thanks...

Forgot the screenshots :(. Power usage can be seen in the top bar. Upper number is total power usage, lower number is dGPU power usage. Any mode that results in high gpu power usage results in loud fans.

Also adding 3 additional screenshots in dual screen mode. External screen connected via DisplayPort and tested on 3 different refresh rates.

Here's some hard data. Connected via USB-C to DP 1.2 port on Samsung U28E510 at 1920 x 1080 @ 60Hz. Lots of watts and heat.

Since it is hot here in So Cal today, my palms are getting sweaty on the palm rest while I am bathed in warm air. It sounds like the ocean with no waves. Nice.

I created an account just to make this one comment and this will be my only comment. To William Kucharski, DPJ and others alike: there is a reason why everyone in this thread got the urge to Google the possibility of this being an issue and end up here. They are not here to randomly complain about Apple; these are people who have spent a lot of money for this product because they believed in it, and they are tirelessly communicating with each other in the hopes that someone would find a workable/temporary solution before or until Apple fixes this issue, so that they can continue to enjoy it for years to come.

Thanks to raimiss’s comment in this thread I was able to set up a temporary safe solution while still being able to use the monitor, until there is a fix from Apple. His findings are: 1) In clamshell mode, refresh speeds 100hz, 120hz, 144hz, 160Hz at full HD or QHD via DisplayPort, and 60hz at 1920x1080 via HDMI draws 5W, while ironically 60Hz or 85hz at any resolution on DisplayPort draws 17W power. 2) The 17W power draw also applies to any refresh rate/resolution combo in non clamshell mode.

These findings alone show that it is not the AMD being more power hungry, etc., or “the TGP for the GPU is 50w, so even if it's drawing 20w that's less than half of what it could draw when working its hardest”. Simply put for you William and DPJ who are commenting with no helpful information, to the point where you are commenting on people’s purchase/return decisions with quotation marks and bold fonts: In clamshell mode via DisplayPort, the computer draws 5W during 100Hz and above refresh rates @FullHD, QHD, and 17W during less than 100Hz refresh rate. Don’t start commenting things like it is completely normal that 60Hz or 85Hz is drawing more than 3 times the wattage than what the 100,120,144Hz is drawing.

My MBP 16" 64GB RAM, 1TB, i9 2.3GHz with 5500M 8GB now runs quietly and the CPU is running 16C cooler when idle, just by switching the monitor to a higher refresh rate to minimum 100Hz and using it in clamshell mode. My laptop sits at a height for proper air flow, and my monitor is a Samsung 27" WQHD 144Hz Curved VA Monitor (LC27JG52QQNXZA).

My lid is closed to the point where it turns on clamshell, so heat can escape from the keyboard as well. When I check the Touch Bar area, the heat doesn't bother me anymore. Haven't done any SMC/NVRAM reset, didn't re-install Catalina, still running 10.15.3. Turned off dynamic wallpaper and TrueTone (lid is almost closed anyways). I still can’t use my monitor in those cool temperatures while in non-clamshell mode, but I am now at least comfortable using my monitor while my MBP is in clamshell mode.

The only area that I agree with William is that we should all contact Apple Support so that they know it. We should inform them about this inconsistency, so that they can fix it and we can have a similar watt usage when we are not using it in clamshell mode, or using it in clamshell mode at 60hz refresh rate (the word similar was for William and DPJ, in case they start writing clamshell and non clamshell can't draw the same power etc.).

For anyone who is lost in those endless pages of comments, read raimiss’s comment that I have screen shot below, try adjusting refresh rate accordingly, notice if there is a significant temperature/wattage increase when using refresh speeds lower than 100Hz or during non clamshell mode, then contact Apple Support to inform them about this inconsistency. I have tried all combos of raimiss’s ( except for 160Hz and 85Hz ones because of my monitor capabilities), and all of his findings apply to mine. 2560x1440 gives the same result as 2560x1080 as well. Not sure about 4K monitors since I don’t own one.

Thank you to everyone who thought that this extra heat and wattage output was not normal and tried coming up with countless solutions (that worked or didn’t work). In the meantime, although not ideal of course, I just hope that many of you have a monitor that can do 2.5K/1080p @ 100Hz and above via DisplayPort, or you have an HDMI port that can do 60Hz at 1080p, so that you can still use your monitor in clamshell mode in cooler temperatures until Apple releases a fix.

Thank you for putting in the time and reading this long comment, I hope that you will all put in the time to inform Apple Support about this finding as soon as possible. Contact them again with your case # if you have already contacted them before; the additional finding that raimiss stated will definitely help them understand the situation better.

Let's all spread the word and get this going! All the best to all of you!

[Edited by Moderator]

Another thing that I sometimes do is when fans go crazy for no particular reason, I change fan control to "Automatic Fan Rules" in iStat, let the fans go down and then revert to using "System Controlled". This has proven to help as well - most of the time fan stay in the lower RPM mode.

TailsDog wrote:

With NO external display, the video runs in VLC. acceptably But get this, it never switches to dGPU. When I manually switch to it, it runs worse with the dGPU.

Very odd.

That is very odd. So only internal display with the dGPU active an 8k video is playing worse than with just the integrated GPU? I will download it and see if the same is happening for me.

DPJ maybe you can test this on your machine, as you have no issues usually? Or as you are a video editor you probably have dealt with 8k content before, has it caused you an issue in the past with the dGPU or does it work fine for you?

Yes, with the iGPU on the built in MBP monitor with VLC it is noticeably smoother when the video pans or moves around. With the dGPU it is not as smooth. I was able to run the video with the dGPU with gfxCardStatus.

Also, with the dGPU the MBP runs hotter and the fans are audible. I've attached some metrics.

You can test it out yourself by watching the videos I linked to earlier. They are 8k h264 drone filmed videos. I used video 0008 which is 3.5gb approximately.

The above is the dGPU. Notice the heat and power draw.

The above is the iGPU. Notice the lower heat, fans, and power draw.

The above at 6:48 is the dGPU and the lower spike at 6:58 is the iGPU.

In closing, I would like to mention that this is the iGPU out performing the dGPU on the "heartbeat" legacy built in display of the 16 MBP. It is running this video/codec better, cooler, and more efficiently.

I would also like to add that running this on my LG Ultrafine 4k external monitor in clamshell mode provides worse performance than on my built in display with either the iGPU or the dGPU. External it's dGPU only as everyone knows.

Having said all this, I am 100% convinced that this iGPU can run external displays. And it can run most of them better, well from an energy efficiency POV at least, than the dGPU.

I don't know what the problem is, but I do believe it's dGPU related. Be it thermals based, driver based, OS X based, I dunno... Here's hoping Apple will at least let us run our external displays with the Intel 630 that we all have and know can power them just fine.

" I really wish I could stop my subscription to these posts now that we are in the process of returning them. "

I think this will help you move on. From the web browser on a computer go to the top left and click on your forum name. A HUD will appear. See my attachment. Click on My Subscriptions. You will be navigated to another screen with all the threads you've subscribed to. From there choose the "MacBook 16-inch Fan Noise" and click on the blue PLUS button to the far right. A box will appear showing FOLLOWING and REPORT. Click FOLLOWING. You will unfollow the thread.

Enjoy your next journey onto Windows 10. 😉

EDIT: i missread the message. It’s 3 external hdmi monitors. I was obly running 2. My bad.

Any source for that? On my 2016mbp i used 2x usb-c to hdmi cables (one satechi cable and one apple multiport adapter) and internal display was always on with no problem. Based on my experience with previous gen macbook pro, its hard to believe in that statement.

Now I'm starting to get a little scared.

I was using my MBP for light browsing, been on for less than 30 minutes and I did a Google search in Brave. Every result that I clicked on opened up a new tab that displayed GPU glitches. I've attached a screenshot below.

Every page looked like this, or had parts that looked like this. I checked the temps, CPU, energy use and everything was normal. I was in clamshell mode.

I then opened up the MBP 16 lid and I dragged the corrupted browser window to the built in display. Exactly the same. I then refreshed. No change, same glitches.

I then opened up Safari and went to the same sites. The websites were displayed with no glitches at all in Safari.

I opened up my 2012 retina MBP and used Brave to go to the same sites and they displayed correctly.

I then unplugged my LG Ultrafine monitor and that switched the GPU back to the built in Intel. I then hit refresh and the websites that were glitching fixed themselves.

I think it's clearly the combination of Brave and the AMD gpu causing this.

Grant Bennet-Alder wrote:

You can't run three legacy displays (such as HDMI) directly with ordinary adapters. At least one needs to use an ACTIVE adapter, because the signals out of the Mac are at lower DisplayPort levels, and there is not enough extra to directly drive three "legacy" displays. An ACTIVE adapter will boost the signals for the third one up to "legacy" display levels.

Just received my base 16" and successfully connected my 3 external displays using basic HDMI adapters from Amazon with no mentions of them being "active". Can you show your source of this limitation?

About the GPU wattage, I have the same results as everyone here. 5W using closed clamshell with a single 1080p@60hz but just opening the lid or adding more displays makes the GPU use 18-21W.

However both fans only runs at 1.7k RPM which is not very noticeable. Temps are averaging at 65 °C during casual web browsing with a Youtube video opened with the 3 externals displays + lid opened.

Still annoyed that Apple is not aknowledging the issue though.

Yes, I'm going to have to call them, as it just happened again. Now it happened in Lightroom, which is an essential app and use case for this machine.

How do I even describe this?

I want to search the forums as well and I'm stuck not knowing what to search for exactly, and frankly a bit overwhelmed. Have you seen this before? Any direction to discussions about it would be appreciated.

Can it be due to the heat issue... the dGPU runs especially hot and thus issues like this are created? I don't know...

I think Tim's machines, that he sent back, had this. I wish I can get a hold of him and ask him about it. I don't think there's a way to private message here, is there?

It does make sense why your system is hot and why your fans are working. You are pulling in almost 80 watts of power. Mine by comparison is 26 watts (UPDATE: in this screenshot it's showing 32). Your graphics card is using 20 watts, so it's not just the graphics card. Something is using lots of energy for that additional energy.

any clue in Activity monitor under energy?

here is mine: