New Graphics Card

I need help finding a new graphics card and have no experience finding a good one, please help.
I will be using this new graphics card for playing video games.
Here are my specs
Operating System Windows 7 Home Premium 64bit
CPU AMD® A8-3800
Chipset AMD A75
Graphic Integrated AMD Radeon HD 6550D
Memory 8 GB
DDR3 at 1333MHz
Expansion Slots 1 x PCI, 1 x PCI-e x 1, 1 x PCI-e x 4, 1 x PCI-e x 16, SATA 6 x SATA 6Gb/s
Storage 1TB
Optical Drive 24x DVD-RW
Wireless Data Network 802.11 b/g/n
LAN 10/100/1000Mbps
Audio Realtek ALC887
High Defination Audio Codec
High Definition 8 Channel Audio
Front I/O Ports 1 x 16 -in-1 Card Reader
1 x Headphone
1 x Microphone
2 x USB 2.0
Back I/O Ports 2 x USB 3.0
6 x USB 2.0
1 x PS/2(Keyboard/Mouse)
1 x DVI-D
1 x HDMI-In
1 x HDMI-Out
1 x VGA(D-Sub)-In
1 x VGA(D-Sub)-Out
1 x RJ45 LAN
1 x 8 Channel Audio
1 x S/PDIF out(Audio jack)
Card Reader 16-in-1: CF/ Micro Drive/ MS/ MS Duo/ MS Pro/ MS Pro Duo/ SD/ MMC/ MMC4.0/ RS-MMC/ RS-MMC4.0/ SDHC/ MS Micro-M2/ Mini SD/ Micro SD/ Mini MMC
Power Supply 300 W
Dimensions 6.8 x 14.2 x 15.8 inch (WxHxD)
9.5 x 18.9 x 20.2 inch (WxHxD) with Carton
Weight 10.5 kg
(17.4 lb)
Software PC-cillin Anti-Virus Trial
Office 2010 starter
nero 9 Essentials
Microsoft Pack
Adobe Acrobat Reader