View Full Version : WiFi slow down when external monitor connected

Jan 4, 2009, 07:29 PM
Did any of you experienced this ? My WiFi slows down or even stops working when external monitor is connected (via the big connector, don't remember it's name, DMI or something like that). Air Rev A, 1.6.

Jan 4, 2009, 09:22 PM
Sorry Leez, but mine is running just the same...

Jan 4, 2009, 10:38 PM
How close is your router to the monitor. Try moving router somewhere else if possible. My ACER 24" is plastic, no change in MBA wifi. I do find G to be more stable than N.

Jan 4, 2009, 10:42 PM
Are you running in clamshell mode? My PowerBook would run in clamshell mode and have troubles with connecting now and then, something about blocking the antenna.

NC MacGuy
Jan 4, 2009, 11:51 PM
I don't have any problem with mine.

Jan 5, 2009, 07:09 AM
Are you closing the lid when you connect to the external monitor? I think it was on MacObserver on a review on the new 24" that closing the lid on the MacBooks will dramatically decrease Wi-Fi strength, so that could be your problem. Other than leaving the lid open I don't know what else to suggest unless you can use a USB Wi-Fi dongle instead of the Wi-Fi built in.

Mar 9, 2013, 10:07 AM
Just wanted to say thanks for letting this issue come up in a Google search!

I was actually searching for wifi interaction with studio monitors as I use my MBA in a recording studio, but it turns out it was my external monitor (screen) through the mini display port that was destroying my wifi!

I was able to duplicate this problem to a T, running Win 7 on Bootcamp on a 2012 MBA:

wifi connection speed at 130 mbps (full signal strength)
plug in external monitor
wifi speed slowly drops to 5.5 mbps over 1-2 minutes (still full signal strength)
unplug external monitor
wifi speed creeps back up to 130 mbps

I had a 720p youtube video loading while I did all this and could watch the progress grind to a halt, and start back up again as soon as I unplugged the monitor (I have a 20.0 mbps connection so normally 720p videos load quickly).

Weird ****! Any ideas as to the physics behind this?

Mar 9, 2013, 11:01 AM
I use my 2011 13" MBA with an old 23" Apple Cinema Display connected about 90% of the time. Never saw anything like this myself. But I might not notice, since all I use wifi for is the internet which is a slow 2.5mb DSL connection (all I can get out here in "the sticks" :) )

I leave the lid open on my MBA with the screen turned off. The fan kicks in too often for my taste if I run it in clamshell mode.