M1 PRO and MAX have issues with ProMotion Display

RAM and CPU are overused when watching Netflix, disney+, and others on full screen.

Ion Utale
3 min readDec 24, 2021


The new M1 processors are awesome and very powerful.

I am very much enjoying my mac.

As a true geek, I like to use the stats monitor and see how many resources I use.

And so after about 1 hour of Netflix, I notice that my RAM was around 24 Gb out of 32Gb.

With WindowServer using most of it 17Gb 🤯

WindowServer is a system service that acts as the liaison between OS X apps and your Mac’s graphics hardware. Basically, if an app wants to draw something on your Mac’s screen, WindowServer is the one telling the graphics card what and where to draw it.

Also, the CPU zone of the mac was hot, but vents were not running.

This is pretty odd, something's not quite right, so I did some research.

The Research

So stats tells me that the windows server is taking most of the memory, like 17Gb

Other people seem to have the same problem as me, it seems related to the fullscreen video and ProMotion display.

Although other people have massive CPU usage, I don’t.

Here is my CPU, RAM, CPU temperature 32 and PMU (Power Management Unit) 52, and the fans are at 2312|2483

Here is my entire list of sensors temperatures

not bad, actually

It seems that using safari to watch videos, the issue does not present itself.
I know that safari does not support 120 Herz yet. You can use this site to test the refresh rate https://www.testufo.com/

Possible issues

ProMotion can run at 120 Herz, for Apple, this is a new technology (even though they are using it for a few years already ).
So running 120 Herz means that the GPU must write double the frame rates to the RAM, and remember that the RAM is unified 🤓.

Ok, it seems that we got our issue, but now how can we fix it?

How to fix it

Go to Settings then to Displays

and change the Refresh Rate to 60 Herz, restart the computer and that is it.

Problem fix, the ram will no longer expand into eating all RAM, nor using all CPU and battery.

Yes, to fix it, we need to remove the best features of these macs. 😥

Thank you for reading and as always,
If you enjoyed please leave a few claps 👏👏👏
As it helps me a lot.

Have a lovely day.



Ion Utale