WindowServer High CPU usage while connected to external monitor - Monterey

Good afternoon nonodev96,

Welcome to the Apple Support Communities!

It sounds like you are experiencing high CPU usage with the WindowServer process in macOS Monterey.

It appears you have been working with Apple on this issue. We would suggest you get back in touch with them to continue troubleshooting.

Contact Apple for support and service

Take care.

I just want to say that I have this problem too. A month ago I decided to update my 2018 MacbookPro to Monterey from Mojave. I 100% regret my decision. My computer feels almost unusable at this point.

I have two external displays, which were working with no problems prior to updating. Now my CPU spikes through the roof when they are connected and I move my mouse around. My webcam video is very choppy during meetings because of the overall high CPU usage.

Other threads have mentioned that this happens when having a mouse plugged in via USB. I ditched my USB mouse and am now using Bluetooth, but the problem remains.

Other threads have mentioned that gaming mice that are polling at a higher rate can cause issues. I have dropped my mouse polling rate to be 120Hz (or maybe 125Hz? I forget..) and this has still not resolved my problem.

My external displays WERE both using HDMI connections just fine when I was running Mojave. However other threads have suggested to try and mitigate this problem with only a single HDMI connection. I am now using a USC-C to DisplayPort for one monitor, and USB-C to HDMI for the second monitor and I still have high CPU use from WindowServer.

I have disconnected one of my external displays and the problem remains even when I'm powering a single display.

I have reset my SMC and the problem still remains.

I'm really disappointed, because this WindowServer CPU issue seems to have been documented back in Big Sur which came out in 2020. Here we are a full OS revision after that, and 2 years later, and this is still a problem. I'm not really sure if I can downgrade back to Mojave, but I think that's my only option.