Hello I have 6th generation HP Probook 450 G3 and I installed Ubuntu 14.04, Unfortunately sound and WiFi don't work. Can someone refer me to the necessary driver links?
As a comment above states try Ubuntu 16.04. Even then if Sound and WiFi don't work I found some links from other users with their problems and solutions.
When review the links below keep in mind some of them are a year old and might recommend something like "upgarde to Ubuntu 15.10" which you should not immediately try. Instead report back here with your status / problems and seek clarification.
This link from HP website lists steps to get sound working under Ubuntu 15.10: (hp.com - ProBook 450 G3 Ubuntu sound)
This link from Arch Linux (Wireless driver for HP ProBook 450 G2) describes the Realtek RTL8723BE WiFi card problems. First ensure you have that card and then follow instructions (How do I get a Realtek RTL8723BE wireless card to work?) in Ask Ubuntu.
I solved by upgrading my ubuntu 14.04 kernal 3.19 to 4.2