Installing radeon graphics card over i915 on ubuntu 14.04

I am running ubuntu 14.04 and did a check to see which card I was using and it returned i915.
I have a radeon graphics card on my laptop, and I was wondering how I go about using this instead of the default i915 that came with ubuntu 14.04. Below is from the terminal after checking which graphics and video driver I was using.

kyletheboss@KyleTheBoss:~$ lspci -vnn | grep VGA -A 12
00:02.0 VGA compatible controller [0300]: Intel Corporation 3rd Gen Core processor Graphics Controller [8086:0166] (rev 09) (prog-if 00 [VGA controller])
 Subsystem: Samsung Electronics Co Ltd Device [144d:c0e6]
 Flags: bus master, fast devsel, latency 0, IRQ 48
 Memory at f7800000 (64-bit, non-prefetchable) [size=4M]
 Memory at d0000000 (64-bit, prefetchable) [size=256M]
 I/O ports at f000 [size=64]
 Expansion ROM at <unassigned> [disabled]
 Capabilities: <access denied>
 Kernel driver in use: i915

00:14.0 USB controller [0c03]: Intel Corporation 7 Series/C210 Series Chipset Family USB xHCI Host Controller [8086:1e31] (rev 04) (prog-if 30 [XHCI])
 Subsystem: Samsung Electronics Co Ltd Device [144d:c0e6]
 Flags: bus master, medium devsel, latency 0, IRQ 43

Basically, how can I find the best driver for my graphics card? I feel like it isn't being used to its full potential.