i bought dell inspiron 3520 four days back and installed windows ,Ubuntu 12.04 64 bit(Dual boot).Sound is coming properly from the speakers. if i connect ear phone,there is no sound.specification:intel i5 3rd gen,RAM:8gb.It works well in windows 7 .
just need to install the required drivers.After this dist-upgrade .Its working fine now.
sudo add-apt-repository ppa:ubuntu-audio-dev/ppa
sudo apt-get update
sudo apt-get dist-upgrade