I recently installed ubuntu 12.04 on my old dell inspiron 1720 laptop. Everything works fine, except that it simply cannot connect to the internet. It appears that even when I plug in the ethernet cable, no internet connection can be established. Wireless does not work either.
All that I can tell you right now is that my network card is a Broadcom bcm4311. If you need any more information, I will try to answer as best as I can using the terminal. Just know that I am new to ubuntu!