Is your 2019 MacBook Pro 16-inch heat up and make a loud noise when it is connected with a 4K external display? Don’t worry, you are not alone. The internet is full of users complaining about the Hot and noisy issue with the MacBook Pro 16 2019 when connected to an external 4K monitor. So what is the main reason behind this issue? Is there any way to deal with it? Here is what we know so far
The Story So far
A large number of users with the 2019 MacBook Pro 16-inch reported that whenever they connect the laptop with a 4k external display, its temperature goes up rapidly while the fan runs at a strangely high speed and making loud noises. Most of the Macs only heat up and have audible fan noise when you severely tax the CPU or GPU. Therefore, the fact that connecting to only ONE 4k external make the 2019 MacBook Pro hot and noisy is really bizarre.
Some users also find that connecting with an external display sometimes triggers a “kernal_task”. It locks up the machine resulting in a reboot that includes lost work.
What Is The Main Reason For This Issue
There is no exact explanation for the hot and noisy issue on the 16-inch 2019 MacBook Pro. Users have done plenty of experiments to find out which is the root of this issue. They’ve used IStats Menus to examine how many watts the system is drawing. As soon as a 4k external is connected, the power consumption jumps up from under 10 watts to around 40 – 60 watts, which is very significant. The testers also run thermal test and fan test here are the result:
- The idle temperature with no external display is about 40 Celcius degree and Fan is spinning at 1800 RPM.
- The idle temperature with a connected external display is about 60-80 Celcius degree while Fan is at 3000 RPM and can bump up to 4000RPM.
Theories say that the machine automatically switches from using the intel-based GPU to the Discrete GPU (the AMD Radeon Pro) when it connects to a monitor. The AMD GPU seems to require more power to work than the intel-GPU. There’s also no way to use the Intel GPU with the external display. Therefore, it makes the MacBook Pro heat up and ramp up its fan.
The affecting users have reported this issue to both Apple and AMD. Apple surely acknowledged the hot and noisy issue on the 2019 MacBook Pro 16-inch when connecting to a 4K external monitor. Unfortunately, it hasn’t provided any actual fix. The company instead claimed that this is simply a bug. It recommends users connect the external display to the other side of their MacBook Pro 16-inch. This workaround does reduce the heat and fan noises for some users, but the rest are still having the same experience.
There is plenty of other workarounds from the communities for this issue. Most users recommended keeping the MacBook Pro in clamshell mode will drastically reduce the heat and noise it makes.
Other users indicated that adjusting the resolution and refresh rate on the external display will improve the situation. Switching from USB-C Dock -> HDMI to USB-C -> DisplayPort cable is also an effective method for this problem.
You can also check out some other methods for dealing with lousy fan noise in our guide here.
Are there any other MacBook Models with the same problem?
Apart from the 2019 16-inch MacBook Pro, Users also reported the same issue is also happening on the early-2020 13-inch and 16-inch MacBook Pro
And that’s what we know so far about the hot and noisy problem on the 2019 16-inch MacBook Pro when connected with a 4K external monitor. If you have any new workarounds for this issue, please share them with us and other users in the comments!