AC 7260 upload channel width stays 20MHz

[GViti1]

Client: Intel AC 7260 or AC 3160, Windows 10 64-bit, driver 18.33.7.2 (05.04.2017) or 18.33.6.2 (19.02.2017 Windows default).

WiFi router: Mikrotik hAP AC-lite (RB952Ui-5ac2nD-TC).

Wifi 802.11AC mode in use.

Connect WiFi where is a good signal strength (-55dBm or better).

Open WiFi router WebFig->Registration http://192.168.88.1/webfig/# Wireless.Registration

Observe Rx (upload) rate (channel width). It is 80MHz.

Run speedtest.net to check upload speed. In my case it is > 90Mbps.

Move the client to poor conditions where signal strength -75dBm or worse.

Wait about 1,,,2min until upload channel width is stable 20MHz.

Go back to position where is a good signal strength.

Upload channel width stays 20MHz and Speedtest shows 52Mbps.

Only way to get upload channel width back 80MHz is to reconnect to the WiFi.network.

Same situation with different computers, and with Windows 8.1 64-bit.

No such a situation with Windows10 phone equiped with WiFi chip AR6320. Upload channel width returns to 80MHz.

Download channel (Tx on router side) width also returns to 80MHz as expected.

See screenshots.

So upload channel width does not return to 80MHz as expected.

The router manufacturer (MikroTik) says that channel width is chosen by client device.

Quetion: is it a bug in the Intel WiFi adapter driver?

[idata]

Hi GVI,

We understand your situation regarding your Intel® Dual Band Wireless-AC 7260 and your Intel® Dual Band Wireless-AC 3160 that you are getting some troubles with the upload speed.

In order to better understand the situation, please provide the following information:

- https://downloadcenter.intel.com/download/25293/Intel-System-Support-Utility-for-Windows- Download Intel® System Support Utility, run the tool and use it to create and save a report with all sections, then add your reply to this thread and use the Advanced editor options to attach the resulting file to your post.

-Please provide us one log when the upload speed is working fine and another log when the upload speed is not working.

-Could you please let us know if you have this situation with 2 different systems or did you upgrade your wireless adapter and got the same result?

Regards,

Junior M.

[GViti1]

See attached files.

File SSU_20MHz.txt created when upload channel width is 20MHz, SSU_80MHz.txt - when 80MHz.

I found situation on 3 different computers. All have Windows 10. Two with AC 7260. One with AC 3160.

In the system used to create SSU reports I have tested another AC 7260 card and same situation.

Also tested with different MikroTik hAP AC lite router. Same situation.

GVI

[idata]

Hi GVI,

Thanks for the Logs provided, based on that we found that your connection rate is very low in both cases. In the 80Mhz your connection rate is 433.33Mbps, this should be closer to 867 Mbps. In the 20Mhz your connection rate is 6Mbps, this is extremely poor. Looking at your settings, all of them are okay. There are too many adapters affected for a hardware issue to be likely. Would it be possible to test the adapters on a different branded routers? Best regards, Junior M.

[GViti1]

The router has single chain 802.11ac 5GHz wireless. So max speed rating is 433Mbps.

Internet connection is 100Mbps. So actual max speeed expeted is some what below 100Mbps.

I have used 2 routers:

https://mikrotik.com/product/RB952Ui-5ac2nD-TC

https://mikrotik.com/product/RB952Ui-5ac2nD

Both have same chipset. I have no other AC router to test.

In 802.11n (HT mode) there are no problems in channel width switching 20/40MHz.

I think the ratings reported in Windows or SSU do not show actual situation.

See one more SSU report in file SSU_20MHz_2.txt made when channel width is 20MHz. Reported speed rate is 433Mbps for recive and transfer.

Router shows that upload is 86Mbps-20MHz only. Download is 433Mbps-80MHz. Signal strength also is good.

Speedtest.net shows redused upload speed.

Windows status shows 433Mbps

GVI

[idata]

Hi GVI,

Thanks for the information provided. Based on the SSU logs, the settings are the same as when you were receiving poor connection rate. Based on this we would like to check the following: -Are you using the latest Firmware for your Router? -Is there any option to toggle your Quality of Service(QoS) or access list settings? You may need to verify this information with your Router Manufacturer. We look forward to hearing back from you. Regards, Junior M.

[GViti1]

Router is running RouterOS 6.40.3 - latest. And no fixes for this situation in next release candidate change log.

https://mikrotik.com/download MikroTik Routers and Wireless - Software

Router configuration is out of the box "Home AP Dual". No ACL or QoS used.

Same situation with other MikroTik hAP AC lite device.

The way to get back upload to 80MHz is simple - just reconnect WiFi.

Download channel width switches normaly. Only upload stuck on 20MHz. Signal strength (-55dBm) and quality is good (>90%).

I have already contacted with MikRotik -Ticket# 2017090222000309.

Router configuration file (rif-file) was reviewed by Microtik.

MikroTik answer is that the channel width is a client device decision and there is nothing to do at router side.

[idata]

Hi GVI,

Thanks for the update. In this case, we recommend you to perform a clean driver installation, please follow the next steps:

We advise you to use the generic driver version of https://downloadcenter.intel.com/download/26924/Wireless-Intel-PROSet-Wireless-Software-and-Drivers-for-Windows-10 Intel® PROSet/Wireless Software and Drivers for Windows® 10 [19.70.0]

1. Go to Control Panel, Programs and Features and Uninstall "Intel® PROSet/Wireless Software", if it is installed. When prompted, choose the option to "Discard settings".

2. In Control Panel, Device Manager, Network Adapters, right click on the Intel® Dual Band Wireless-AC 7260 and Uninstall it. Make sure you mark the option to "Delete the driver software for this device". 3. Reboot the PC or scan for hardware changes, check device manager and if an older wireless driver is detected and installed, repeat the actions to uninstall and delete it as well. Repeat this process until the OS does not allow deleting the driver, or until the controller shows as Unknown Device. 4. Remove temporary files: Press the Windows Key + R to open the run box. Type Cleanmgr.exe. Press OK. Select the main drive, usually C:\. Check Temporary Files and uncheck everything else. Press OK. 5. Install the Intel Wireless driver. During the first steps of PROSet/Wireless installation, make sure to customize the installation and install all driver components.

Please bear in mind that our best recommendation is to connect the devices affected to another wireless network in order to confirm if the issue persists.

Regards,

Junior M.

[GViti1]

I made driver uninstallation until the unremovable version (Windows original) - 17.15.0.5, 22.02.2015.

And I found a different behavior of this driver: I can not get it to stable 20MHz where signal strength is -80dBm only. 20MHz is rarely for very short time.

So this driver solves stuck on 20MHz.

I will check the latest driver (18.33.7.2) once more and some earlier drivers too.

In attached file SSU_80MHz_17_15_0_5.txt system report with this old driver.

GVI

[idata]

Hi GVI,

Thanks for the information provided. Please keep in mind that 20MHz channel width is more stable so if there is interference the Router will choose it in order to avoid it, 80MHz will provide you more bandwidth but RF interference would affect the quality of the signal. You could test by choosing a different wireless channel. For more information you can check the following links :-https://www.lifewire.com/best-wifi-channels-for-your-network-818278 How to Choose The Best Wi-Fi Channels for Your Network-https://fossbytes.com/how-to-increase-wi-fi-speed-choose-correct-wi-fi-channel/ How To Increase Wi-Fi Speed by Choosing Correct Wi-Fi ChannelNOTE: Any links provided for third party tools or sites are offered for your convenience and should not be viewed as an endorsement by Intel® of the content, products, or services offered there. We do not offer support for any third party tool mentioned here.Regards,Junior M.

[GViti1]

Driver 17.15.0.5 channel width returns to 80MHz. Speedtest result is appropriate. No changes in this.

I have already tested different channls (36, 52) and even in rural area.

The router automaticaly selecting the channel with the least number of other transmitters.

In the place with good signal strength (50...55dBm), signal quality is >90%.

We expect that at this position channel width should be 80MHz as it is when WiFi is connected.

And it is when WiFi is reconnected after stuck on 20MHz. And only upload channel is affected. Download is ok.

So all that means that stuck on 20MHz is not rised by some interference.

The regeresion starts in a driver version after 17.15.0.5 and before 18.33.6.2.

I am gooing to test these driver versions to find the version where the regresion starts.

GVI

[idata]

Hi GVI,

Thanks for letting us know that you are testing on your end the drivers, please share the results as soon as you are able to find any information. We are testing on our end as well, we will keep you updated with the results or any suggestions. We look forward to hearing back from you. Regards, Junior M.

[GViti1]

I have tested drivers within WiFi packages 18.32.0 - 19.50.1 (version - date DD.MM.YYYY):

18.32.0.5 - 22.12.2015 Ok

18.33.0.2 - 28.01.2016 Ok

18.33.3.2 - 03.05.2016 Ok

18.33.5.1 - 09.10.2016 Ok

18.33.6.2 - 19.02.2017 Upload stuck on 20MHz.

So, the regresion starts from driver 18.33.6.2, package 19.50.1.

This is the driver I have already mentioned as affected at the begining of this discussion.

The last good WiFi driver version for AC 7260/3160 is 18.33.5.1, included in WiFi packages 19.20.3 - 19.40.0.

Screenshots for driver 18.33.5.1

Upload (Rx from router side) width is 20MHz at week signal:

Upload channel width returns to 80MHz at good signal strength as expected:

Screenshots for driver 18.33.6.2

Switching to 20MHz at week signal:

Stuck on 20MHz at good signal strength:

See SSU reports for both drivers in attached files.

GVI

[idata]

Hi GVI,

Thanks for the update, we will bring this information to our additional resources.We would let you know when we have an update on this situation. Best regards, Junior M.

[GViti1]

Actualy all drivers starting from version 18.11.0.8 (package 18.11.0) suffer from upload stuck on 20MHz.

Last driver without the stuck is 17.16.0.4 (in package 17.16.0). It is the next after 17.15.0.5 that I found as a first good driver.

For both these 17.x drivers I can't get upload in stable 20MHz mode. At -85dBm upload rate is shown 6...24Mbps without frequency specified.

When signal strength is -80dBm or better upload returns to 80MHz mode.

Previously I do not found the situation for some 18.x drivers because bandwidth tester was generating upload traffic somehow preventing the stuck on 20MHz.

GVI

[ChrisC_Intel]

Hi GVI,

We are currently working with engineering to understand this behavior, we will be in contact with you as soon as we have any updates on this.

Regards,

-Chris

[Junior_M_Intel]

Hi GVI,

We still investigating this situation, we would post any updates as soon as we have them.

Regards,

[GViti1]

Thanks for status update!

GVI

[idata]

HI GVI,

We still investigating this situation. However, we need to verify the following information: 1. Are you having this issue in an enterprise environment or is this a personal situation? 2. Could you please confirm how many systems are affected?We look forward to hearing back from you. Regards, Junior M.

[GViti1]

Hi,

It is a home environment.

3 systems affected:

1) Dell Inspiron 5558, Windows 10 1703 64-bit, AC-3160

2) Dell Inspiron 3542, Windows 10 1703 64-bit, AC-7260 (with two different AC-7260 cards tested)

3) Some HP Computer, Windows 10 1703, AC-7260 (currently not available for testing)

Tested today once more. Both Inspirons stuck on 20MHz at good signal strength:

WiFi drivers currently used: 18.33.3.2, 18.33.9.3.

GVI