Need opinions on hardware from Newegg.com

[pillowslap]

Im trying to build a computer for the first time. Im pretty good on a computer but not when it comes to building one. I just need to know if these pieces work together and are a good price. total price= $690.92

Western Digital Caviar Blue WD5000KSRTL 500GB 7200 RPM SATA 3.0Gb/s 3.5" Internal Hard Drive- $69.99

HIS H485FM512H Radeon HD 4850 512MB 256-bit GDDR3 PCI Express 2.0 x16 HDCP Ready CrossFireX Support Video Card- $102.99

OCZ Fatal1ty OCZ550FTY 550W ATX12V v2.2 / EPS12V SLI Ready 80 PLUS Certified Modular Active PFC Power Supply- $64.99

Kingston HyperX 4GB (2 x 2GB) 240-Pin DDR2 SDRAM DDR2 800 (PC2 6400) Dual Channel Kit Desktop Memory Model KHX6400D2LLK2/4G- $99.99

GIGABYTE GA-EP45-UD3L LGA 775 Intel P45 ATX Intel Motherboard- $89.99

Intel Core 2 Duo E8400 Wolfdale 3.0GHz LGA 775 65W Dual-Core Processor BX80570E8400- $167.99

ZALMAN CNPS9500 AT 2 Ball CPU Cooling Fan/Heatsink- $49.99

 

[Atomic Rooster]

That's not bad at all. What will be it's main use?

 

[pillowslap]

Probably just some COD4, League of legends, not sure. For now this will be fine but if i need to upgrade later i will.