Hi: Welcome to Linux Questions.
As of jessie, the need for the proprietary drivers is pretty much over--
Just to let you know ahead of time, the AMD Catalyst 14.9 driver is not capatible with the Gnome DE.
When I was running Ubuntu the proprietary driver made my graphics unstable and buggy so I had to uninstall it.
I learned from that not to install it on my Debian system when I was running it.
The kernel should be providing a module/driver for your current on board card.