One of the confusing issues is that people say, "I'm only using 15% of my CPU, the fans should not be coming on."
What they don't realize, is that using 1 core running at turbo speeds is only going to show up as 15% of the CPU, but draw enough power and create enough heat to trigger the fans!
Another thing that some of these posters are not aware of, is that running these temperature/fan speed monitoring applications can use quite a bit of power! They're drawing all these fancy graphs, the applications are usually poorly optimized. Even the Mac OS Activity Monitor is a hog in Catalina for some reason and can take 15-20% of a CPU all by itself.
And that doesn't even take into consideration all the other apps people have running. You can see in their screenshots or menu bar they have Dropbox, 3rd party wireless keyboard/mouse programs, they might have 10 things running in just their menubars! They need to look in the Activity Monitor's Power section to see what the real culprit is.
Plugging an external monitor into your MacBook will enable the dGPU and that will create more power draw, this is nothing new:
It's the workload, not the monitors you have plugged in.
I posted a picture in the MacRumors thread with 4 externals (4K, 2x1440, 1x1080) plugged into my base model 16" and it idled in the 50 degree range with no audible fan noise. Once I started streaming video and opening apps, the fans then started, as expected.
My 2019 15" mbpro makes quite a bit of noise on login screen with nothing connected to it. It's not a made up issue. USB 2.0 devices disconnect randomly which is a no-go for musicians. Touch bar freezes. The list goes on. I'd abandon it a long time ago but music software is macs first. Plus Logic is decent. It's so sad that they don't give a damn because market takes a while to adjust.
That touchbar freezing issue is a pet peeve of mine. It's been happening for years now. I've personally witnessed over it perhaps 10 times over multiple hardware/OS revisions.
Perhaps it's time for Apple to admit defeat and just build a watchdog service that runs every 30 seconds and if things aren't working: kill and restart whatever process and/or driver that runs the touch bar.
I agree with what you are saying up until you say nothing is wrong with the fan coming on at a 15% cpu load.
regardless of what is really happening to take that 15% load, if the fan comes on that strong, it is not a proper thermal design. As a contrast, I have an 8 core iMac Pro. It can run full throttle and I rarely if ever hear the fan and it is much quieter than my 2018 6 core macbook pro. Of course a 27" home chassis has much more room to dissapate heat, but that is the point. Shoving oversized processors with multiple cores that generate lots of heat is at odds with Jony Ive's add more thinness campaign. I am now in a position where I use my macbook for dev and more intensive uses and its so damn annoying that Im seriously considering getting rid of it. I was at a client site this week, and my laptop was constantly the but of the joke, and disruptive to 5 other people working in a conference room. Sorry, but that just sucks...
15% load can mean a single i9 core boosting to 4.8-5ghz. The OP is correct. When I use a single threaded program that is keeping a core pinned at 100% why would it be unreasonable for the fan to be on?
I dont care if the fan is on. I care that the fan is egregiously on. It is probably 95-100db on. That means that the macbook is fundamentally unable to manage the heat load it generates. It would be one thing if I were in the middle of the desert outside at 100degreeF conditions. But I was indoors and the ambient temperature was probably 68F. Again, I dont care if the fan runs, I just dont want to hear it, and I dont want the fan to be loud enough that everyone worries that my laptop is going to "catch fire", "Take off", "heat the room", and a half dozen other comments that were made at a client site. I bought a macbook to have nice hardware that I dont have to worry about...
Your reply comes off a little condescending. You don't know the technical ability of the people posting in the forum, or what they realize or not.
It doesn't take any special qualifications for a person to hear the the fan turning on more often on their new MBP than with their old MBP running the same work loads.
Fair point, but the issue that might be pointing to this being a problem is that the same thing didn't happen on a laptop from 4 years ago:
> We DID NOT notice this on our 2015 MacBooks...
So, if a much older laptop with lower specs wasn't engaging the fan while performing the same tasks, something may very well be wrong (at some level: I have no diagnosis for what the issue could be).
Agreed. I'm not an electrical engineer, but I'm curious: Isn't it inherently harder to cool a single turbo'ing core the smaller the core is? Say a core is 1mm by 1mm, and generates 45W of heat in that area, then say it's 0.5mm by 0.5mm and generates the same heat. Apologies in advance for any inaccuracies or misphrasing of the question.
macOS (Activity Monitor) reports utilization normalized to a single core, so 15% really means 15% of a single core. On the MBP the scale goes up to 1600%.
I understand that - I did mean CPU core and not an entire CPU. Still a ridiculous amount of power when the previous versions of Mac OS didn't have that kind of usage in Activity Monitor.
One of the confusing issues is that people say, "I'm only using 15% of my CPU, the fans should not be coming on."
What they don't realize, is that using 1 core running at turbo speeds is only going to show up as 15% of the CPU, but draw enough power and create enough heat to trigger the fans!
Another thing that some of these posters are not aware of, is that running these temperature/fan speed monitoring applications can use quite a bit of power! They're drawing all these fancy graphs, the applications are usually poorly optimized. Even the Mac OS Activity Monitor is a hog in Catalina for some reason and can take 15-20% of a CPU all by itself.
And that doesn't even take into consideration all the other apps people have running. You can see in their screenshots or menu bar they have Dropbox, 3rd party wireless keyboard/mouse programs, they might have 10 things running in just their menubars! They need to look in the Activity Monitor's Power section to see what the real culprit is.
Plugging an external monitor into your MacBook will enable the dGPU and that will create more power draw, this is nothing new:
https://i.imgur.com/9KmLPMX.png
It's the workload, not the monitors you have plugged in.
I posted a picture in the MacRumors thread with 4 externals (4K, 2x1440, 1x1080) plugged into my base model 16" and it idled in the 50 degree range with no audible fan noise. Once I started streaming video and opening apps, the fans then started, as expected.