@_cc 

Hello, you can enter AX73 in the dialog box, then you will see it in the dropdown list as follows:

Regarding the 5G speed, what if you just enable the Smart Connect, and leave the channel width settings by default? Is the speed normal? 

BTW, how do you want to modify the wireless settings on the AX73, was there any issue that you want to change the settings? Please provide more details as you can, then we can try to figure it out.

!! Naruhodo, no wonder there is just a few products on list, lol. Thanks for guiding o/.

Channel width preset of smart connects is auto select, right? I got random lag all the time.

I can't even play YouTube video smoothly;;. That is the reason I'm trying to change wifi setting.

When I tried to google the lag reason, I found TP-Link website said change channel width should fixed it.

https://www.tp-link.com/en/support/faq/2170/

@_cc 

Are you saying you can play YouTube smoothly when connecting to the 2.4G network? Generally, when Smart Connect is enabled on the router, it allows the router to automatically assign connected devices to the Wi-Fi band that provides the fastest speed.

Are you playing YouTube videos on a laptop or on a phone? What's the distance between the router and the laptop/phone? 5G WiFi is faster but provides a shorter range than 2.4G, you can try to move closer and test again.

@Kevin_Z 

Are you saying you can play YouTube smoothly when connecting to the 2.4G network? 

I got normal LAN/wifi speed in 2.4g with any width& 

　　　　　　　　　　　　　  5G with 20 or 160 MHz.

When router auto change to 5G with 40 or 80MHz, all speed test results can't over 2Mbps.

Generally, when Smart Connect is enabled on the router, it allows the router to automatically assign connected devices to the Wi-Fi band that provides the fastest speed.

Are you playing YouTube videos on a laptop or on a phone? What's the distance between the router and the laptop/phone? 5G WiFi is faster but provides a shorter range than 2.4G, you can try to move closer and test again.

I always test connection speed beside the router or LAN. Can I make router don't change channel width when a smart connection is on?

@_cc 

That's weird. What is the device you are testing the 5G connection? Phone or laptop? What is the OS or model of the 5G adapter?

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