Find out if Windows 10 is limiting your Internet speed

[Jordan]

Find out if Windows 10 is limiting your Internet speed

 

If you noticed an Internet speed drop after upgrading to the latest version of Windows 10, the following troubleshooting guide may help resolve it.

It may be particularly useful if the Internet speed was fine on previous versions of Windows, and is no longer after the upgrade to Windows 10 Anniversary Update edition.

Microsoft introduced a feature called Window Auto-Tuning back in Windows Vista, and has made it part of any newer version of Windows as well.

Set to on by default, it is designed to improve performance for programs that receive TCP data over a network.

While data transfers should be more efficient as a general rule, users may experience slower than usual data transfer speeds under certain conditions or even connectivity issues.

Managing Window Auto-Tuning in Windows 10

 

The first thing you may want to do is check the status of Window Auto-Tuning. If it is turned off for instance, it is likely that it is not the case for the slow downs, but if it is set, it may very well be the culprit.

Note: you don't need administrative privileges for running the command above, but you will need them for modifying the Window Auto-Tuning parameter.

1. Tap on the Windows-key, type cmd.exe, hold down Shift and Ctrl keys, and hit enter.
2. Confirm the UAC prompt that opens.
3. Run the command netsh interface tcp show global.

Locate the "Receive Window Auto-Tuning Level" value under TCP Global Parameters. If it is not set to disabled, it is being used by Windows to optimize TCP connections.

You may want to disable the feature to run connection tests and see if it is the cause for the limited Internet speed that you are getting out of the connection.

Run the following command to disable Window Auto-Tuning on Windows 10:

• netsh int tcp set global autotuninglevel=disabled

You get ok as verification that the value was set correctly. You may verify this by running netsh interface tcp show global again.

 

 

Once disabled, start downloads just like before and monitor the speeds that you get. You may want to fire up a P2P client, Usenet program, FTP client or server program to find out if disabling Auto-Tuning Level did resolve the issue.

If it did not, you may want to turn it on again. This is done by running the following command:

• netsh int tcp set global autotuninglevel=normal

Ok should be returned again to indicate that the new value was set correctly. It is recommended to check the global values again to make sure that is indeed the case.

If you want to know more about Window Auto-Tuning, check out the excellent analysis of the feature here.

 

 

SOURCE

[Holmes]

TCP optimizer from speedguide.net is best when tuning this:

 

www.speedguide.net

 

THis is a very good site.

[petok]

And this is best tweaking and fast stable speed. I have playing tweak with setting and got +370 kb/s speed from real speed. Just tweak one by one, not once all.

Spoiler

http://www.speedguide.net/articles/windows-8-10-2012-server-tcpip-tweaks-5077

http://www.speedguide.net/articles/network-adapter-optimization-3449

 

[leo007]

Mine is set to normal, no problem here.

[Jordan]

Similar article about Windows 10 Anniversary Update (That's why i posted it here instead of creating a new topic for it)

 

 

Windows 10 Anniversary Update might limit your Internet speed

 

Windows 10 Anniversary Update, the major feature update for Windows 10, comes with a feature called Window Auto-Tuning which is enabled by default. This feature is intended to improve performance of apps which receive TCP packets over a network. Under certain conditions, this feature can reduce your Internet speed. Here is how to check if you are affected by this issue and fix it if required.

The Window Auto-Tuning was introduced in Windows Vista. There, it was not enabled by default. In Windows 10 Anniversary Update, it is enabled out of the box to manage your network transfer data. While it should serve well for most of users, in some cases it can reduce your network performance.

To check out the state of Windows Auto-Tuning, you can do the following.

1. Open an elevated command prompt.
2. Type or paste the following command:

   netsh interface tcp show global

   

3. In the command output, look for the line "Receive Windows Auto-Tuning Level". If its value says "normal", this means the feature is enabled. If your Internet speed is notable slow, then you can try to disable it.
4. To disable Window Auto-Tuning, type the following command:

   netsh int tcp set global autotuninglevel=disabled

   After that, test your Internet speed. If you were affected by the incorrect behavior of the feature, you should get the improved network performance(thanks Martin).

5. If your network performance was not changed or even become worse, you can re-enable Window Auto-Tuning by typing the following command:

   netsh int tcp set global autotuninglevel=normal

SOURCE