3

I am helping a friend troubleshoot her new Lenovo Yoga 2, running a fresh install of Ubuntu 14.04. She's getting kicked off of wireless networks a lot, and her connection is super slow. I'm running 14.04 on a Lenovo X1 and using the same wireless network and not having any trouble.

When I run nm-tool I see (among other things):

Capabilities:
   Speed:           54 Mb/s

She sees:

Capabilities:
   Speed:           9 Mb/s

Similarly, iwconfig shows a much slower connection for her:

hilary@hilary:~$ iwconfig
lo        no wireless extensions.
wlan0     IEEE 802.11bgn  ESSID:"Young Turnip"  
          Mode:Managed  Frequency:2.437 GHz  Access Point: 00:22:6B:87:D6:6B   
          Bit Rate=11 Mb/s   Tx-Power=16 dBm   
          Retry  long limit:7   RTS thr:off   Fragment thr:off
          Power Management:on
          Link Quality=34/70  Signal level=-76 dBm  
          Rx invalid nwid:0  Rx invalid crypt:0  Rx invalid frag:0
          Tx excessive retries:1  Invalid misc:126   Missed beacon:0

I see Bit Rate=54 Mb/s when I run iwconfig.

I spotted this question: https://askubuntu.com/questions/387922/slow-wireless-connection-on-lenovo But I'm not clear on what he's actually disabling there.

Per My wireless/WiFi connection does not work. What information is needed to diagnose the issue?, here are the full diagnostics: script results

How do we troubleshoot this?

Community
  • 1
Amanda
  • 9,333
  • Why is this flagged as too broad? I realize I need help narrowing down the problem, but it is a very real problem that is making it very hard for her to run Ubuntu. – Amanda Jun 25 '14 at 17:29
  • Sunspots? You're connecting to an 802.11B WAP? You're too far away from the WAP? – dobey Jun 25 '14 at 17:30
  • We're connected to the same wireless network, it works fine for me and is absurdly slow for her. We're sitting a foot apart. – Amanda Jun 25 '14 at 17:30
  • 2
    Too broad because "why is foo slow?" is too broad. To narrow things down requires discussion, and Ask Ubuntu is not a discussion forum (Ubuntu Forums would be a good place to discuss perhaps). A single WAP can provide support for a broad range of 802.11 wireless specifications. B is rated around 11 MB/s and G is 54 MB/s. A WAP may provide A/B/G/N access, and one laptop might connect to N, with another to B. – dobey Jun 25 '14 at 17:33
  • The question you've found, slow wireless on lenovo, might be spot on. Try the first command to see if disabling 11n makes a difference. If it helps, the second one will make the change permanent. – mikewhatever Jun 25 '14 at 18:29
  • @mikewhatever now it just won't connect at all. Tries, disconnects. Over and over. – Amanda Jun 25 '14 at 18:39
  • 1
    I see. A reboot should get you back to the original settings. If you do want to troubleshoot it, post a thread on the http://ubuntuforums.org, it is more suitable for back and forth exchange, and I hope we'll be able to help. – mikewhatever Jun 25 '14 at 20:21
  • @mikewhatever Actually, UbuntuForums isn't much help either. – Amanda Jun 26 '14 at 22:31
  • You're not supposed to need to do this, but it does help my wireless. Enter the command sudo iw reg set US - this is temporary, until the next reboot. – Charles Green Sep 06 '14 at 14:25
  • @Amanda did you solve this? I have the same problem: Wireless card unstable on Lenovo Yoga 2 Pro What was inside the (deleted) answer you posted? – rubo77 Sep 06 '14 at 14:26
  • @rubo77 Still having issues, sadly. – Amanda Sep 07 '14 at 01:15
  • @Amanda Is this still an issue? – amanthethy Oct 25 '14 at 12:21

1 Answers1

0

  1. Maybe it make a difference if you disable the power save options with:

    sudo iw dev wlan0 set power_save off

  2. Also you can try if it makes a difference if you disable the 11n extension with the following:

    sudo su
echo "options iwlwifi 11n_disable=1" >> /etc/modprobe.d/iwlwifi.conf

    You need to reboot after this.

You can monitor the speed with

 watch -d -c "sudo nm-tool |grep -i speed "
rubo77
  • 32,486