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2019 Macbook air lagging with external Monitor

Dear Community,


I would like to kindly ask about my Problem.

Is it normal, when I connect an external monitor to my mac then it starts lagging, and the menu slows down? I use normally an 27" Dell monitor.


Thank you in advance.



MacBook Air 13″, macOS 10.15

Posted on May 27, 2020 12:53 AM

Reply
Question marked as Top-ranking reply

Posted on May 28, 2020 12:58 AM

I have a 2019 MacBook Air and I use a 27 inch Samsung external monitor directly connected from USB-C to USB-C.

I have had no lagging issues. The user interface behaves quite pleasing actually. I keep my MacBook Air's lid closed. Not sure whether you are using both screens and using mirror mode or extended mode.


3 Things to Try-


  1. Open System Preferences ➔ Displays ➔ Resolution - CHECK Default for Display. If that does not solve things then-
  2. Reset SMC by following the directions applicable to your MacBook Air here ➔ How to Reset SMC. If that does not solve things then-
  3. Reset NVRAM/PRAM by following the directions applicable to your MacBook Air here ➔ How to Reset NVRAM/PRAM.


Axel F.


4 replies
Question marked as Top-ranking reply

May 28, 2020 12:58 AM in response to coder_

I have a 2019 MacBook Air and I use a 27 inch Samsung external monitor directly connected from USB-C to USB-C.

I have had no lagging issues. The user interface behaves quite pleasing actually. I keep my MacBook Air's lid closed. Not sure whether you are using both screens and using mirror mode or extended mode.


3 Things to Try-


  1. Open System Preferences ➔ Displays ➔ Resolution - CHECK Default for Display. If that does not solve things then-
  2. Reset SMC by following the directions applicable to your MacBook Air here ➔ How to Reset SMC. If that does not solve things then-
  3. Reset NVRAM/PRAM by following the directions applicable to your MacBook Air here ➔ How to Reset NVRAM/PRAM.


Axel F.


Jun 9, 2020 10:18 AM in response to coder_

I was having problems for months with my MBPro Mid-2012 15" (first Retina model) and external Japanese monitor (21.5"). Fan blasting constantly, lagging, browsers locking up. Tried everything, including upgrading from High Sierra to Catalina but no go.


The one tip that resolved it all was setting the resolutions for both monitors exactly the same. I couldn't do that through System Preferences/Displays/Scaled option. I used a third-party app to precisely select 1080p (in my case) for both displays and voila, fan shut off, no lagging, all fine.


Why it wasn't an issue in the past with the same monitor I have no idea, but once the problems started nothing would resolve them. Hope it helps.

2019 Macbook air lagging with external Monitor

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