由於系統驅動問題，DELL M4800安裝Ubuntu 14.04找不到wifi模塊，需要更新驅動。步驟如下：
Update of the driver :
sudo apt-get update
sudo apt-get --reinstall install bcmwl-kernel-source
如果還沒找到wifi，在官網下載最新的驅動，編譯。按照驅動的readme.txt 如下：
http://www.broadcom.com/docs/linux_s...30.223.248.txt
# rmmod wl
Did a find on all wk.ko on my computer and renamed all (except the newly created
by the makefile)
# mv <path-to-prev-driver>/wl.ko <path-to-prev-driver>/wl.ko.orig
# cp wl.ko <path-to-prev-driver>/wl.ko
# depmod
# modprobe wl
Got some errors so I did this :
# rmmod wl
and run (from the place where I copied the new wl.ko file):
# modprobe cfg80211
Then:
# insmod wl.ko
After a reboot of my machine and could activate wireless from the network
icon (desktop right upper corner), and could connect to my private (wpa/wpa2)
network
with password.