MacBook 16-inch Fan Noise

brycesteiner wrote:

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

I had issue with a BenQ Sw320.

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

I had problems before installing such software.

We can say whether it is observed or not if and only if we see the real wattage of the GPU. I have the same configuration and use the same dock and tested my configuration with 3 different displays: HD, 2k and 4k, any combination of two of them + closed lid = 5w, opening the lid = 20w.

@brycesteiner It would be great if you could install iStat Menu at least to check the power consumption, it has 14 days trial.

Moreover, as I've already reported before, using USB-C to HDMI adapters does not help at all. In my case, only TB3 connection to the dock + closing the lid brings 5w. All tested monitors are connected to the dock using DP or HDMI.

I read here that someone had said it wasn't observed with two connected external displays, but I am not sure if that was in clamshell mode or with the lid open. I haven't personally tried it myself, but if it is the case, I would be tempted to pick up another monitor. I like to use the keyboard on the MacBook since it is a pain adjusting back and forth to the keyboard.

This is interesting, I can't see the post. Was it reported that there is less power consumption from the GPU when using 2 external monitors? Would be interesting to see if it is in clamshell mode or not. I don't have another monitor to test it right now.

Yes, you have the same problem as everyone else. Look at the Radeon High Side parameter-20.47 W! If you continue to work in the same mode that your fans will rise to 4500rpm and maybe higher! And they won't stop!

This is a slightly different scenario - I offer it mainly as a comparison: Right now I'm running a 15" 2015 MBP - the prior generation, but with the top end GPU R9 and CPU. In order to prevent the extreme noise of the fan being a constant issue, I have 3rd party software (TG Pro) run the fans all the time at just below audible levels - this helps keep it from heating up to the point where it has to increase fan speed enough to be a loudness issue, which on this laptop is around 4000 RPM.

Right now, the fans are pretty silent (I'm not tasking the CPU or GPU at all), and the CPU is at 124F, while the GPU is at 121F. This is greatly aided by the fact that my office is cold in winter.

I realize this isn't the same laptop, but it might be useful info to report at what temperatures (CPU/GPU) the fan level goes above audible. It seems like the "danger point" typically runs between 140F and 180F. That being said, if this happens instantly upon hooking up external monitors, then it's probably not heat related.

Sorry - just saw that you did exactly that. I had to convert from Celcius to Farenheit, but yeah - you are running hot - above 150F. I'd say it's reasonable for fans to kick in at 150F, so the main question is why did your laptop get so hot?

Even though my system is running great, I did notice the voltage numbers were higher when the screen was plugged in directly. I had it plugged in this way for an hour and the fans never did race but they were on. The system temperature was actually lower.

This is an interesting and helpful utility. I'll check out some more and see what other circumstances makes this change and report it.

I wonder if this is just a matter of AMD driver issue. Is this the difference when automatic graphic switching is enabled? Perhaps the AMD is sleep at 7 volts but at 20 volts it's enabled?

fmorga wrote:

Summary of the Situation:

3- It looks like all MBP 16 are defected.

Once again, simply because something does not work the way you (or others) want it to does not make the product in itself defective.

Yes the fans run, but no one here has shown the unit goes into thermal shutdown either, so whether the power draw is a bug or not the MBP is handling the thermal load.

Once again, if anyone does NOT experience this problem, please STAY AWAY (especially those, who not uses external displays, yes you)!

The product is defective, I returned my machine because this EXACT ISSUE, one of my friends as well (same issue, fans 100% once plugged to an external display).

The issue is REAL.

Good summary @fmorga!

Yes, most of us here agree that the problem is the GPU, but watching a video on Safari or browsing the web shouldn't stress the GPU, but for some reason having an external monitor causes the GPU to draw 20 watts and after a few minutes the machine gets really hot and the fans go from 2000 RPM to 4000 (sometimes even 4500 RPM), just for browsing the web, that is not acceptable for a machine like this one, but I think it's a software/driver issue because is not consistent, sometimes doing exactly the same thing I can get the machine to stay cool for 30 minutes up to 45 minutes and sometimes just 5 minutes after connecting the external monitor the machine goes crazy, an even when the machine goes crazy without doing anything different sometimes the fans go down to 2200 RPM without any logic, because I check the activity monitor and iStats and there is no process taking CPU or GPU usage.

That's really useful information, at least we know that if we buy a dock it will help with the fan noise. I guess I will have to spend an extra $300 if I want to be able to use the external monitor without having the machine going crazy.

Thanks for taking the time to test your Mac and share that info.

One last question, do you use the CalDigit TS3+ dock to power your Mac? Because I was checking the specs on the CallDigit dock and the maximum power consumption is 85w and the power adapter that comes with the MacBook Pro 16-inch is 96W, I read in another forum that some people using docks with less than 96W were having problems with the 16-inch, one person mentioned that the battery was not fully charging while using the dock so after using the machine for 8-10 hours he only had like 60% battery.

Using a power supply for mbp 16 with less power can negatively affect the battery life!!! There is also a drop in the power of the device when powered with less power!!! You must use the original charger with the power 96W!!!