5 years ago
  Realtek (WIFI card/adapter/dongle)
  Mint (older version)
  Doesn't work as expected
What doesn't work:

no wifi is visible

What was done to make it work:

the first doing is, install working firmware, follow the describtion:

german (better): http://forum.ubuntuusers.de/topic/kein-internet-seit-ubuntu-13-10-auf-lenovo-b54/
english: http://www.programering.com/a/MzN4cjMwATg.html

the wifi is still not working, this issue is a ideapad modul.
There is a module called "ideapad_laptop" that prevents the wifi module to start.

remove ideapad_laptop:
sudo rmmod ideapad_laptop

now its working fine :-)

blacklist this with:
echo "blacklist ideapad_laptop" | sudo tee -a /etc/modprobe.d/blacklist-ideapad.conf

if you loosing connection copy this lines and execute:
echo "options rtl8723be fwlps=0" | sudo tee /etc/modprobe.d/rtl8723be.conf