MacBook 16-inch Fan Noise

Many here claimed that just connecting a monitor and letting it sit idle would cause any MBP 16’s fans to go crazy, and that’s clearly not the case.

I also disagree “most use Chrome;” I use Safari exclusively and use Chrome on macOS maybe monthly at best, mostly because it can even cause the fans on my iMac to spin up.

Many people in this 205 page thread claim to have the issue yet you claim you don't therefore you conclude that clearly issue doesn't exist?

Wow.

Honestly I'm waiting for anyone other than you to speak up that the issue doesn't exist with screen open + external monitor attached.

There have been several others who have posted similar experiences over the course of this thread.

I did not say the issue didn't exist, what I said is that my experiences disprove the claim that they all do it regardless of the display.

That means that there is some other mechanism at play here that needs to be understood; my only guesses are a combination of my use of Mini DisplayPort and the fact that my monitors are both lower resolution than the built-in display.

Today I did some additional testing and I'm pretty sure that Apple and AMD can fix this issue with a software update.

I tested a program on 10.15.4 and the Radeon GPU was using 12 watts and then I tested the same program on another version and it was using 32 watts, same exact program and same exact hardware but a HUGE difference in wattage, on 10.15.4 the fans never went above 2000 RPM, on the other version the fans went crazy.

I've just got home from Apple with the 16" with 5600M — so far so good on the dual 4k monitors.

Will keep testing and keep you updated. Does anyone know why iStat doesn't work now? It works fine on the 16" with 5500M — but on here it's showing "no sensors found".

So whilst I can't see what's going on it's definitely silent! Will see if it crashes on wake from sleep.

ryunokokoro wrote:

I think we're in a battle of "I said; you said". Let's bring in a neutral third party here. Specifically, the following is macOS browser usage over the last 13 months:

Chrome:• 54.42%

Safari:• 38.85%

Firefox:• 5.54%

Since Chrome isn't an Apple product, it's not Apple's fault if your machine heats up running Google's wildly inefficient code.

Part of my point, William, is that your usage of Safari in your "benchmark tests" is effectively meaningless. The tests you ran would have Safari sipping so little power as to effectively equate to the laptop sitting idle. Most people do not use their laptops idle - they use a MacBook Pro for professional purposes, including [and especially these days] video calls and screen sharing.

That's absolutely hilarious: don't use Apple's software, it's meaningless, use this third party software known to be a resource hog and that makes desk side Mac Pros run hot and has for its entire life as a product and see if your MBP heats - that's your argument?

I thought people were claiming just connecting a monitor and letting the MBP 16 sit idle would cause my fans to "go crazy." Now I have to be running specific software that uses excessive amounts of CPU to help heat the machine past what the GPU does alone?

Try not using Chrome - really for anything, there are very rarely reasons to, the only one I have found is Apple's decision to not allow HTTP 0.9 connections for media playback.

If your laptop idles with no fans but starts to spin up after a few minutes of more than trivial CPU usage, then I'd suggest that your machine suffers the very same issue that everyone here is reporting. Your machine may simply have a "lucky CPU/GPU" in that the CPU and/or GPU placed in your machine happened to be particularly "good" coming out of the fabrication binning process.

Streaming full screen HD video isn't "trivial," it's one of the more CPU-intensive thing we ask computers to do, video calls/conferences are another, editing 4K video streams is yet another.

The excuses as to why my machine doesn't do this seem to be coming fast and furious now, as if it's some magical unicorn despite no one else being able to prove their MBP 16 does see this issue when driving the same monitor in the same way.

Millions of Dell U2717Ds and Apple 30" Cinema Display are out there, it can't be hard for someone to give it a shot.

Note at 2400 RPM, my fans weren't even audible in my environment, even with my ear on the machine itself.

The basic question here is "how much does it take for your machine to start turning on its fans"?

I've never heard my MBP 16's fans under any circumstance aside from while preparing to install a new macOS update, which isn't surprising as CPU usage often reaches 380% or more during that period.

Once again, that doesn't mean other's don't experience the issue, especially when driving 4K displays.

I love your line of logic iTech23, but I can't help but comment that, while your test proves that software can make the problem worse, it doesn't provide much comfort that software can also make the problem better than it currently is. I am not ordinarily so pessimistic, but Apple is giving me plenty of reasons to be that way...

I wanted to comment on the last post but it was deleted for some reason, I'm having the same exact problem, my machine works "fine" on 10.15.4 but it's having problems on 10.15.5 or 10.15.3, the only way I can use my machine with an external monitor right now is with 10.15.4 but I want to update to the latest version to take advantage of the new battery feature.

Thank you so much for sharing. is your MBP the 8 cores model?.

If so, would you please be so kind as to also try using a plug-ins heavy Logic Pro X session?.

With monitors and without monitors if possible, please.

I'm very keen to find out what the fans noise is like, without any monitors connected.

I went to the Apple store to test it but they didn't have any 8 cores, i9 models on display.

I'm stuck with an old 2012 quad-core model. would love to upgrade but I can not live with the fans noise.

Keep us updated on the 5600M

I think it's bad news for the 5300/5500M if it's fixed with the 5600M. That means it's a hardware issue and no fix could be coming for the 5300/5500M.

Apple is probably going to keep claiming attaching an external monitor activating dyson vacuum mode is "acting normally" :(

Max Tech posted a video about this. External displays will cause your fans to ramp up. The fact that it causes fans to ramp up has nothing to do specifically with the 16" MacBook Pro, but rather with Apple's discrete GPU and external display implementations. The fact that it's louder on the 16" MacBook Pro when this happens than its 15" predecessors has to do with the fact that the 16" MacBook Pro's thermal system prioritizes running the fans to keep the machine cooler than it does keeping it quieter (and hotter as a result). That's a good thing.

The Max Tech video that explains this can be found here: https://www.youtube.com/watch?v=EkmdHVfk4XE

Well, the fact that the computer gets 10c hotter + ramping fans to 3500rpm~ on idle when an external display is connected is not a good thing.

Doing anything that pushes the cpu even for a short periods of time, like compiling code, will ramp up the fans almost to max and the laptop get hot enough to be uncomfortable using the builtin keyboard.

Having to disable TB to be able to make the laptop more usable regarding hot is not acceptable, when older models and the newer 5600m one doesn't suffer from this.

I'm using a Viewsonic Display with 2560x1440 pc at 59,88 hz. When I'm using the standard resolution my fans are going crazy. When I switch to 1080p the fans are silent at all. Do you think its worth it to try another display who allows exact 60hz?

I tried different cabels but its always at 59,88hz....

I don’t have the time to respond to most of your post at the moment, but I never expected anyone to run out and buy a 30” Cinema Display or Dell U2717, but certainly a lot of people are likely to have one or the other lying around if they have been a computer user for a long time.

Therefore, across the many people reading this thread, odds are at least one other person has one and can try it if they so choose.

Note also that some of the workloads you propose cause the fans on an iMac or MacPro to spin up as well as they are very CPU-intensive and I would think having the fans spin up doing the same on a laptop would be a given.

Has anyone tried if the products at svalt.com make any difference in solving this problem? The Cooling Stand S Pro looks promising and I'd give it a try if I was living in the US. Unfortunately I am from Europe though, so there is no way for me to return it in case it does not help.