500-700$ Gaming build

[gospag]

Hello everyone !
First of all I'm wondering about why everyone is suggesting Intel build for gaming? ;\
I would like to build an AMD rig, but i accept any Intel build too, which fits the budget range, and have the same performance, or even above.
Approximate Purchase Date: October-November 2012
Budget Range: around 500$ would be nice. [I'm living in Romania, and here the prices are a BIT higher than on Newegg.]
System Usage from Most to Least Important: Mainly for gaming.
Parts Not Required: Keyboard, Mouse, Case, Monitor, Speakers.
Preferred Website(s) for Parts: Don't have any, i just need an idea about what should i buy, or maybe websites which are shipping internationally.
Country: Romania
Parts Preferences: AMD/Ati would be great
Overclocking: maybe
SLI or Crossfire: No
Monitor Resolution: 1920*1080

My selections:
AMD FX-4100 Zambezi 3.6GHz (3.8GHz Turbo) Socket AM3+ 95W Quad-Core Desktop Processor FD4100WMGUSBX

GIGABYTE GA-970A-D3 AM3+ AMD 970 SATA 6Gb/s USB 3.0 ATX AMD Motherboard

Patriot Intel Extreme Master, Limited Edition 8GB (2 x 4GB) 240-Pin DDR3 SDRAM DDR3 1600 (PC3 12800) Desktop Memory Model PVI38G160C9K

PC Power and Cooling Silencer MK III 500W Modular 80PLUS Bronze Power Supply compatible with Intel Sandy Bridge Core i3 i5 i7 and AMD Phenom

Seagate Barracuda 7200.9 ST3500641AS-RK 500GB 7200 RPM 16MB Cache SATA 3.0Gb/s 3.5" Internal Hard Drive

About Video cards I'm not sure.

SAPPHIRE Radeon HD 7770 GHz Edition 1GB 128-bit GDDR5 PCI Express 3.0 x16 HDCP Ready Video Card ( 11201-00-20G)
or
SAPPHIRE Radeon HD 6850 1GB 256-bit GDDR5 PCI Express 2.1 x16 HDCP Ready CrossFireX Support Video Card with Eyefinity (100315L )
or
SAPPHIRE Radeon HD 6870 1GB 256-bit GDDR5 PCI Express 2.1 x16 HDCP Ready CrossFireX Support Video Card (100314-3L )

Thanks for help and suggestions in advance.

 

[zared619]

Here is a decent build.
http://pcpartpicker.com/p/hSPH