Advice on New Build

Hi , Im Planing on making this build and I would like some advice and I would also like to know if these are compatible with each other. Btw i am trying to make a Gaming Computer from this. Oh and this is my first build.

Approximate Purchase Date: June , 15 , 2011

Budget Range: (e.g.: 600-800) 500 - 600

System Usage from Most to Least Important: Gaming

Parts Not Required: Monitor , Keyboard , Mouse

Preferred Website(s) for Parts: Amazon

Country of Origin: US?

Parts Preferences: AMD Processor , Nvidia Graphics

Overclocking: Yes

SLI or Crossfire: Maybe

Monitor Resolution: 1280x1024

Additional Comments: Quiet and Fast

Hard Drive:Seagate Barracuda 7200.12 500 GB 7200RPM SATA 6Gb/s with NCQ 16MB Cache 3.5-Inch Internal Bare-OEM Drives ST3500413AS
Power Supply :Coolmax M-500B 500W Eps Power Supply with 5 Sata Connectors ATX12V & EPS12V
Case:NZXT Beta Evo Classic Series ATX Mid Tower steel chassis CS-NT-BETA-EVO (Black )
Video Card :PNY nVidia GeForce GTX550 Ti 1GB DDR5 2DVI/Mini HDMI PCI-Express Video Card VCGGTX550TXPB
DVDLiteon 24X DVDrw Sata Retail
Memory :Kingston ValueRAM 4 GB Kit (2x2 GB Modules) 1333MHz PC3-1066 DDR3 DIMM Desktop Memory KVR1333D3N9K2/4G
CPU Cooler :Cooler Master X Dream 4 Aluminum Extrusion Fins CPU Cooler - (RR-LEE-L911-GP)
Processor :AMD CPU HDZ955FBGMBOX Phenom II X4 955 Black Edition 3.2GHz AM3 125W Retail
Motherboard :MSI Socket AM3/GeForce 6150SE/DDR3/A&V&GbE/MATX Motherboard GF615M-P33