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(2019) 16" is HOT & NOISY with an external monitor! :(
- Thread starter Appledoesnotlisten
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well... Its 131 Pages. Most of the posta are Just
Well... 131 pages
and yes, I'm following this thread for sometime now and I didn't notice any solution.
Yeah it's a hell of a issue. For now I'm currently using it in clamshell mode to avoid some type of issues like that
I guess there is a partial solution using switchresX https://forums.macrumors.com/thread...r.2211747/page-75?post=28546067#post-28546067well... Its 131 Pages. Most of the posta are Just
Well... 131 pages
+ forcing 60Hz seems to work for some. [edit: instead 59.something which AMD driver forces by default i guess?]
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Thank you very much. However from this and a few next posts I can see this only works with 1 external monitor + clamshell mode.
I'm using my macbook with an iPad as an external display very often. In my home / office the macbook is in open mode connected to 27" 4k monitor.
My current macbook pro 13" 2018 is perfect for this, except I'm starting to think it's a bit too small - 16" would be perfect
I'm in the UK, we're having a bit of a heatwave at the moment.
Today, my 16" MacBook cannot function properly when plugged in to an external monitor. kernel_task starts eating loads of CPU which is apparently meant to manage heat https://support.apple.com/en-gb/HT207359
I've never had a MacBook before that I can't use in some weather, but it appears I do now.
Today, my 16" MacBook cannot function properly when plugged in to an external monitor. kernel_task starts eating loads of CPU which is apparently meant to manage heat https://support.apple.com/en-gb/HT207359
I've never had a MacBook before that I can't use in some weather, but it appears I do now.
Big Sur definitely hasn't helped. If I run the computer without any TB modifications and do intensive multitasking throughout the day, there comes a time when heat control takes over and CPU is suddenly downclocked way below 2 GHZ, even to 1 GHz range, and things slow down to a crawl while the fans howl. After a few minutes, the temperature creeps down and the CPU is "released" to do some actual work. A MacBook-dictated coffee break. Checking these numbers with Intel Power Gadget.
It can tolerate high speeds for quite a long time, probably up to an hour. That may be the reason, why it doesn't show up as a problem in YouTube benchmark videos. But the whole body becomes increasingly hot, and eventually there's throttling that brings the CPU down to its knees.
It seems obvious that the 20 W minimum dGPU consumption aceis contributing to the accelerated throttling threshold. I'm not doing GPU-intensive work.
I did a diagnostic with Apple Support online, and the computer is fine, works as expected. They promised to capture the feedback and put it forward. I'd suggest anyone under warranty to call at least once and add a +1 to the case.
Not sure what's the next step. Since the Mac is technically OK, there's nothing to fix. It may soon be the time to switch over to a desktop model again.
Welcome to the club. Happened to me as well, two days in a row, when the room is uncomfortably warm, maybe 24-25 °C.
Things just suddenly slow down to a crawl. Intel Power Gadget shows the CPU chugging along between 1-2 GHz for a few minutes, and then everything is back to normal.
During that time the whole chassis was very hot. Maybe it takes into account many more than just the CPU temp, before it goes into limp mode.
The extra 20 W heat brought to you by the friendly dGPU certainly isn’t helping, if the headroom is already tight due to ambient temperature.
It can tolerate high speeds for quite a long time, probably up to an hour. That may be the reason, why it doesn't show up as a problem in YouTube benchmark videos. But the whole body becomes increasingly hot, and eventually there's throttling that brings the CPU down to its knees.
It seems obvious that the 20 W minimum dGPU consumption aceis contributing to the accelerated throttling threshold. I'm not doing GPU-intensive work.
I did a diagnostic with Apple Support online, and the computer is fine, works as expected. They promised to capture the feedback and put it forward. I'd suggest anyone under warranty to call at least once and add a +1 to the case.
Not sure what's the next step. Since the Mac is technically OK, there's nothing to fix. It may soon be the time to switch over to a desktop model again.
Welcome to the club. Happened to me as well, two days in a row, when the room is uncomfortably warm, maybe 24-25 °C.
Things just suddenly slow down to a crawl. Intel Power Gadget shows the CPU chugging along between 1-2 GHz for a few minutes, and then everything is back to normal.
During that time the whole chassis was very hot. Maybe it takes into account many more than just the CPU temp, before it goes into limp mode.
The extra 20 W heat brought to you by the friendly dGPU certainly isn’t helping, if the headroom is already tight due to ambient temperature.
Hey guys,
I've just made a video to send to the engineering dept at Apple as they don't seem to be able to understand the problem and respond accordingly. After being escalated through various levels of support, and explaining the problem in detail, the support team finally sent the report through to engineering, who replied to say "this is expected behaviour, the reason you don't experience the problem in Clamshell mode is that it switches to the integrated GPU." As far as I'm aware an external monitor always forces the Dedicated graphics, and you'd think they would know that, but anyway that's another story! The fact is in my case I'm always using the DGPU, so their explanation is meaningless. So I've made this video to try and demonstrate the basics to them:
Here's a basic summary:
I'm using a Macbook Pro 16" 2019 (Core i9 2.3ghz, 16gb RAM, AMD Radeon 5500M 4GB)
Using an external display with the Macbook Pro 16" causes the macbook to become really hot (69 to 75 degrees), and the fans to spin up to 3000rpm and become noisy.
The reason for this is that when you use an external display as well as the laptop display, the power drawn by the DGPU (Dedicated GPU) jumps from 4w to 17w.
Use the laptop display alone (using the DGPU), it only draws around 4w.
If I run a 1080p external display in clamshell mode, again the DGPU only draws 4w.
If I run 2 x 1080p external monitors in clamshell mode, the DGPU draws 5w.
Open the laptop and it jumps to 19w.
So where is this all this extra wattage draw coming from? It seems very clear that it shouldn't be needed to run the two displays, so it suggests a problem. A driver problem perhaps?
The support told me that the engineering department have given their assessment now, but they will pass on my reply. So we shall see... it really doesn't seem like anyone has had an intelligent response from them yet.
Anyway, I'm managing to run two 1080p monitors in clamshell mode at 5w gpu draw and temps staying under 60. With Turbo Boost disabled. So that's a workable solution for now.
I've just made a video to send to the engineering dept at Apple as they don't seem to be able to understand the problem and respond accordingly. After being escalated through various levels of support, and explaining the problem in detail, the support team finally sent the report through to engineering, who replied to say "this is expected behaviour, the reason you don't experience the problem in Clamshell mode is that it switches to the integrated GPU." As far as I'm aware an external monitor always forces the Dedicated graphics, and you'd think they would know that, but anyway that's another story! The fact is in my case I'm always using the DGPU, so their explanation is meaningless. So I've made this video to try and demonstrate the basics to them:
Here's a basic summary:
I'm using a Macbook Pro 16" 2019 (Core i9 2.3ghz, 16gb RAM, AMD Radeon 5500M 4GB)
Using an external display with the Macbook Pro 16" causes the macbook to become really hot (69 to 75 degrees), and the fans to spin up to 3000rpm and become noisy.
The reason for this is that when you use an external display as well as the laptop display, the power drawn by the DGPU (Dedicated GPU) jumps from 4w to 17w.
Use the laptop display alone (using the DGPU), it only draws around 4w.
If I run a 1080p external display in clamshell mode, again the DGPU only draws 4w.
If I run 2 x 1080p external monitors in clamshell mode, the DGPU draws 5w.
Open the laptop and it jumps to 19w.
So where is this all this extra wattage draw coming from? It seems very clear that it shouldn't be needed to run the two displays, so it suggests a problem. A driver problem perhaps?
The support told me that the engineering department have given their assessment now, but they will pass on my reply. So we shall see... it really doesn't seem like anyone has had an intelligent response from them yet.
Anyway, I'm managing to run two 1080p monitors in clamshell mode at 5w gpu draw and temps staying under 60. With Turbo Boost disabled. So that's a workable solution for now.
It seems "acting dumb" is a standard procedure in such cases. IMO it's obvious Apple monitors forums closely (especially as big and as active as this one) - it's a gold mine of consumer feedback! My bet is they know exactly what's going on. Sadly.
I'm starting to wonder if this isn't some serious design flaw...
It shouldn't be too hard or too expensive to develop an improved graphic driver, so I don't know what's stopping them...
that's interesting that you can actually run two externals.
I run one 2K and then no matter what I do, adding extra 1080p goes into 19W.
This is direct proof of the issue. How is it possible that running two separate 1080p monitors (4M pixels) results in a 5 watt dGPU power draw, but a *single monitor* at 1440p (3.6M pixels) results in a 20 watt power draw?? Even worse, running that 1440p display at downscaled 1080p still results in 20 watts! [with identical workflows/computing demands]
How can they not acknowledge this??
Well... 131 pages
Because there's no definitive solution. Let me please summarize the learnings from this thread.
1. Use Displayport or USB-C/Thunderbolt 3 over HDMI
2. Prefer cables over adapters (e.g. USB-C to Displayport cable over buying a separate adapter)
3. Disable TurboBoost if the task at hand doesn't demand the extra capability.
4. Charge the MacBook on the right side and connect the extra monitor to the left side
5. Depending on the monitor you can play around with SwitchResX and the refresh rates. In some circumstances it helped to lower the power draw in clamshell mode.
6. Buy a stand for the MacBook in clamshell mode (heat reasons).
7. The last option would be to play around with Macs Fan Control and customize the fan settings. You should probably know what you are doing.
For the sake of completeness there are certain hacks available.
1. Use only clamshell mode with 1 monitor or just the 16" screen
2. Buy the 5600 dGPU BTO (Build-to-order)
3. Buy an eGPU
4. Buy the 13" if you don't need the GPU or high computing power of the Hexa- or Octacore.
What would be really interesting, whether there's a difference when using Windows via Bootcamp compared to MacOS.
I just read a few reports saying that it's either marginally better or slightly worse.
Maybe someone using Windows on the 16" MacBook wants to chime in.
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I tried installing windows 10 under Bootcamp as I read on here that it could be better. I also installed the modded AMD Radeon Windows drivers that were recommended as the best for the macbook 16". I couldn't find an equivalent software to iStats that showed GPU power draw, so wasn't able to confirm exactly what was going on, but I definitely didn't notice any improvement... it still ran at over 60 degrees c when using an external monitor. If anything it was slightly worse in terms of fans running fast all the time.
Big whisky for you for this summarize!
What I want is just a macbook, who can run 2x 4k monitor in claimshall mode AND macbook that I can take with me to the client and run it with an iPad as mobile-external-display.
Currently for this the best solution is to use two different mac devices: iMac + 4k display and macbook pro 13" (I notice that the gpu builded in isn't enough for 2x 4k monitor).
Ehh apple. Macbook pro 16" supposed to be -the best macbook ever- but in fact it's kinda useless... unless you are not using external display at all.
Been using the laptop without ext monitor and power for the evening. It works so well in this setup that I'll give it one more chance as a desktop hub before selling it: Cooler Master Ergostand III. It's a 6-level stand that has a fan with a diameter of a soccer ball: 230 mm. It runs at 500-800 RPM (should be quiet) and moves more than 200 cubic meters of air per hour. I don't expect it to be a silver bullet for the fan noise, but it'd be great if the thermal throttling under long-term moderate load would subside. Will report any findings.
There's an Ergostand IV, but it has a smaller fan with higher RPM (noise potential), so went with the model 3. It should arrive in a couple of days.
There's an Ergostand IV, but it has a smaller fan with higher RPM (noise potential), so went with the model 3. It should arrive in a couple of days.
The 13" actually supports 2 4k monitors @60Hz. https://support.apple.com/en-us/HT211191
Depending on the tasks at hand the monitor might lag, since there's only an iGPU available.
However, the hardware of every current notebook will be utilized with this extensive setup.
Not only that, if its 1080p, its fine, but if its 1440p, you will see the problem.
Macs Fan Control is also available on Windows via Bootcamp and can do that AFAIK.