As I wanted to upgrade my wifi connection to N standard I bought EW-7811UN wireless adapter. My ISP provides 100 Mb/s, my wifi router supports N.

The problem is I'm not sure how to make EW-7811UN running on my Ubuntu 14.04 and how to configure it in a way it provides faster wireless connection than 20 Mb/s (which is what I get on my current built-in wireless card).

I tried to install Edimax drivers which gave no result as the installation crashes with errors.

I tried this solution https://askubuntu.com/a/612651 but it looks like the adapter is still not being used by default.

I started to play with drivers, but I did not really understand the process, so it was like shooting in the dark. I finally walked thru steps listed in this answer -> https://askubuntu.com/a/521367/496720 and ended up with nothing

WiFi Info Script Link: http://paste.ubuntu.com/14609460/

Is here anyone willing to help me with setup of this adapter in a way it uses N-WiFi connection?


Is the performance of the internal wireless improved if you install the correct driver?

sudo apt-get install firmware-b43-installer
sudo apt-get purge bcmwl-kernel-source

Remove the USB, reboot and let us hear your report.

The connection speed reported by iwconfig and therefor by Network Manager, is notoriously imprecise. My card currently reports 1 Mbps but will happily download at the maximum available from my ISP. Please test with speedtest.net.

Checking your paste results, I see no obvious reason that either device won't achieve higher speeds. I have three suggestions that may be helpful.

First, I suggest you blacklist the driver for the internal in order to test the USB. From a terminal:

sudo -i
echo "blacklist b43"  >>  /etc/modprobe.d/blacklist.conf
echo "blacklist ssb"  >>  /etc/modprobe.d/blacklist.conf
modprobe -r b43
modprobe -r ssb

Second, I recommend that your regulatory domain be set explicitly. Check yours:

sudo iw reg get

If you get 00, that is a one-size-maybe-fits-all setting. Find yours here: http://en.wikipedia.org/wiki/ISO_3166-1_alpha-2 Then set it temporarily:

sudo iw reg set IS

Of course, substitute your country code if not Iceland. Set it permanently:

gksudo gedit /etc/default/crda

Use nano or kate or leafpad if you don't have the text editor gedit.

Change the last line to read:


Proofread carefully, save and close the text editor.

Finally, check the settings in the router. WPA2-AES is preferred; not any WPA and WPA2 mixed mode and certainly not TKIP. Second, if your router is capable of N speeds, you may have better connectivity with a channel width of 20 MHz in the 2.4 GHz band instead of automatic 20/40 MHz, although it is likely to affect N speeds. I also have better luck with a fixed channel, either 1, 6 or 11, rather than automatic channel selection. Also, be certain the router is not set to use N speeds only; auto B, G and N is preferred. After making these changes, reboot the router.

  • Done it. No change of performance noticed. 20 Mb/s was checked via speedtest.net and I rechecked it now after this operation - no significant changes (now its around 17 Mb/s) actual infroscript output: paste.ubuntu.com/14632206 – Nepu Jan 24 '16 at 14:43
  • We still see the USB loaded and possibly interfering. – chili555 Jan 24 '16 at 15:01
  • USB removed > reboot > speedtest.net results 16.88/9.82; actual infoscript output: paste.ubuntu.com/14636610 – Nepu Jan 24 '16 at 15:44
  • Please see my edit above in a few moments. – chili555 Jan 24 '16 at 21:49
  • I blacklisted internal wireless drivers, checked the adapter on speedtest.net and it looks that all works perfectly fine. Connection speed raised significantly up to 50/10. This result is more than satisfying for me. @chili555 thank you for your assistance! – Nepu Jan 25 '16 at 22:07

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