Intel AX210 wifi card slow on 5ghz band when using channel 44

[Ree9]

Hello,

I have a weird issue with my Intel AX210 based wifi card.  When it's connected to the 5ghz band and the router is set to use channel 44, the connection is horribly slow (sometimes 10s of megabits per second, but other times less than 1 mbps).  But if the router is set to use channel 157, the connection is just fine and I get speeds up to the 500 mbps range.

I have tried two different routers, and I have tried the wifi card in two different PCs, and the results are 100% reproducible.  After realizing the card was the common denominator, I bought a different wifi card, but it turns out it is also AX210 based and has the exact same issue.

So I believe this rules out the routers, and it rules out the PCs, and it rules out the card being defective, which leads me to believe it is driver related.  I read that a lot of people are having driver issues, and tried some of the things that were suggested in their threads (clean installing the latest version, installing an older version, etc), and none of that has helped.

I also read that you'll want SSU logs, so I'm attaching one where I'm using channel 157 and another using channel 44.  You'll notice 157 was captured while remoted into the machine, which is how I normally use it.  After switching to channel 44 the remote connection was completely unusable so I had to go down to run the scan from the PC directly.

I know you may be wondering why I don't just stick to channel 157 if it works so well.  My ISP-provided router is a wifi 6 router with a 2.5gpbs lan port, but the channel selection is fixed on Auto and cannot be changed, so some days it randomly picks 157 and all is good, and other days it randomly picks 44 and I need to reboot it several times before I luck out and get 157 again.  The third-party router I'm currently using let's me pick channel 157, but it's only wifi 5 with 1gbps lan ports, so both the wireless and wired speeds are slower.  I could definitely buy a newer third-party router with wifi 6 and 2.5gbps ports, but I'd rather avoid the expense and have the AX210 card work properly!

Thanks for any help you can provide.

[AceOfSpades45682]

I tried to look at your Scan logs file and I see that you have a Cisco AnyConnect Secure Mobility Client Virtual Miniport Adapter for Windows x64 I think this is a kind of VPN and this could be one of the reasons why you're experiencing slow connection on 5GHz band. Try to disable it and see what happens. If persists you can do a clean installation of your Wi-Fi drivers It's clear that you tested with 2 different routers and tried the Wi-Fi card on two different PCs. Could you please also review the below links for additional wireless settings and set them accordingly to your environment and router configuration. Please review based on the wireless standard and network band that you are using:

• Recommended Settings for 802.11ax Connectivity
• Recommended Settings for 802.11ac Connectivity
• Recommended Settings for 802.11n Connectivity

In addition, please test changing the power management options following the steps in the below link. For instance, you may try the Maximum Performance option. Power Management Settings for Intel® Wireless Adapters

Can you check if the authentication is set to WPA 2 or WPA 3? Go to Settings > Network & Internet > Network and Sharing Center >  Set up a new connection or network > Select Manually connect to a wireless network in the Set Up a Connection or Network wizard > Next > enter your network's name > test with WPA 2 and WPA 3. Additionally, when you try the clean install of the wireless drivers, make sure that you are not connected to an ethernet cable, and repeat the uninstall steps until the e option to Delete the driver software for this device is greyed out: https://www.intel.com/content/www/us/en/support/articles/000022173/network-and-io/wireless.html

hope it works

Perkins...

[Ree9]

Thanks for your suggestions.  I've tried each of them, but unfortunately with no improvement.

For Cisco AnyConnect, you are correct this is a VPN client.  It is usually in the disabled state, but just to confirm it's not the cause I completely uninstalled it.

I tried several clean installations of the wifi drivers yesterday, but tried again today just to be sure.

The router I'm currently using is only wifi 5, so I confirmed my settings match the recommended 802.11ac settings.

I also tried with each of the different power settings (originally was set to Maximum, which is what I've set it back to now).

Authentication was using WPA 2.  I discovered my router supports WPA 3 so I tried that too, with no difference.

No ethernet cable is connected.

I also reboot the pc after every change, just to be on the safe side.

While making the WPA change I noticed that channel 44 and 157 offer different transmit powers (23dBm vs 30dBm).  So I tried lowering channel 157 to use the same 23dBm that channel 44 is limited to, but speeds were still fast on 157 using lower transmit power.

Also while making the change I noticed the RX/TX rate of my connection differed from channel 44 to 157.  On 157 it's pretty much constant, showing these values:

650.0 Mbit/s, 80 MHz, VHT-MCS 7, VHT-NSS 2, Short GI
468.0 Mbit/s, 80 MHz, VHT-MCS 5, VHT-NSS 2

But then on 44 it's constantly changing, for example here's three outputs I was able to take a screencap of:

26.0 Mbit/s, 20 MHz, VHT-MCS 3, VHT-NSS 1
81.0 Mbit/s, 40 MHz, VHT-MCS 4, VHT-NSS 1

or

240.0 Mbit/s, 40 MHz, VHT-MCS 5, VHT-NSS 2, Short GI
81.0 Mbit/s, 40 MHz, VHT-MCS 4, VHT-NSS 1

or

6.0 Mbit/s, 20 MHz
54.0 Mbit/s, 40 MHz, VHT-MCS 3, VHT-NSS 1

Not sure if that's helpful or indicative of anything.

[AllStars]

Hello there Ree9, have you considered performing a network reset? I suspect there may be issues related to your channel width. For optimal performance and compatibility, it's advisable to enable support for all channel widths. Configuring for 40MHz or 80MHz only can prevent legacy devices that support only 20MHz from connecting to the access point.

[Ree9]

Thanks for the suggestion, I wasn't aware of that feature.  Just tried a network reset now, with no improvement.

For channel width, I'm not restricting channel widths.  The different channel widths indicated in my previous message were happening automatically, not from me changing anything.

[Ree9]

Another detail to add: I booted into an Ubuntu 24.04 Live CD environment, and things work perfectly.  The speeds are slower on channel 44 than on channel 157, I guess because of the lower transmit power maybe?  But the connection is solid and I'm able to remote into other machines without constant disconnections, which is what happens if I try to do the same in Windows.