Looking for advice on this $500 gaming build

[Flux00]

This will be my first build and I'm looking to keep it around or preferably less than $500. My main use will be gaming but I would also like to have an HDMI for video, although it's not a big priority. The screen resolution I plan on using is 1680x1050.

Here's what I am considering:

Motherboard:
ASUS M4A785-M AM3/AM2+/AM2 AMD 785G HDMI Micro ATX AMD Motherboard

CPU:
AMD Athlon II X3 450 Rana 3.2GHz 3 x 512KB L2 Cache Socket AM3 95W Triple-Core Desktop Processor ADX450WFGMBOX

Hard Drive:
Western Digital Caviar Blue WD1600AAJS 160GB 7200 RPM 8MB Cache SATA 3.0Gb/s 3.5" Internal Hard Drive -Bare Drive

GPU:
XFX HD-577A-ZNFC Radeon HD 5770 (Juniper XT) 1GB 128-bit GDDR5 PCI Express 2.0 x16 HDCP Ready CrossFireX Support Video Card

RAM:
G.SKILL 4GB (2 x 2GB) 240-Pin DDR2 SDRAM DDR2 800 (PC2 6400) Dual Channel Kit Desktop Memory Model F2-6400CL5D-4GBPQ

PSU:
Ultra LSP550 550-Watt Power Supply - ATX, SATA-Ready, SLI-Ready, 135mm Fan

Case:
APEVIA X-DREAMER3-BK Black Metal ATX Mid Tower Computer Case

I left out an optical drive because I plan on using an external usb dvd-r, is that a bad idea?

Would this be a decent gaming build for the price or should I just scrap it altogether? I don't necessarily have my heart set on anything so any advice on changing parts for better performance would be appreciated.

Thanks in advance.

 

[batuchka]

Fresh builds go AM3/DDR3 as the sun has gone down on DDR2 platforms with all current and incoming platforms running on DDR3 so @ the $500ish price point

Items off Egg $333AR

Items off Microcenter $170 (965BE + MSI 785G-E53)
http://www.microcenter.com/specials/promotions/AMDbundlePROMO.html

$503AR Grand Total

 

[mattius92]

you need to switch to an AM3 setup with DDR3 memory. AM3 is faster, better and it supports DDR3 which is almost twice as fast as the best DDR2 memory.

Look up MSI and ASUS AM3 mobos, and the Athlon II x3 will work for you.

Also you would want to look into a Samsung Spinpoint F4 for your Hard Drive.

 

[Flux00]

Thank you for the awesome help/info, much appreciated.

 

[Flux00]

Best answer selected by Flux00.

 

[batuchka]

Yep happy shopping/building and u are welcomed ^^