First build for budget gaming

[peteysmooth]

I'd like to get a new computer for playing Starcraft II and Civilization V. I primarily play games on console (haven't played PC games since Civ IV was new) so I doubt I will be upgrading this much to play other games in the next few years but you never know.

I have a 20" 1600x1200 monitor, as well as keyboard/mouse/DVD drive. But I'm looking to purchase everything else for my new computer.

Ideally I'd spend as little as possible and originally was hoping to get away with $400-$500. But it seems I need to spend more as I don't think I can get hold of a "free" OS and don't want these games to be super lame. So let's say I have a somewhat soft ~$600 budget.

This is what I'm thinking of to get the most bang for my buck since I don't want to spend tons. I'd love feedback on whether or not it makes sense to downgrade or upgrade things or if any of my choices are just dumb. I'm a bit worried if I wait some of these combos will leave me spending more overall but I also don't have to buy anything and could wait 1-3 months if prices may get significantly better for the gpu/cpu.

I'm excited about a new comp so thanks for any help!

 

[ScrewySqrl]

By playing with combos (I even reused some of yours), or going with simpler low-cost components, I got it down to $603.92


1 ASRock 880GM-LE AM3 AMD 880G Micro ATX AMD Motherboard
$59.99

1 Mushkin Enhanced Essentials 4GB (2 x 2GB) 240-Pin DDR3 SDRAM DDR3 1333 (PC3 10666) Dual Channel Kit Desktop Memory Model 996586
$72.99

1 AMD Athlon II X4 640 Propus 3.0GHz Socket AM3 95W Quad-Core Desktop Processor ADX640WFGMBOX
$102.99

1 Rosewill Blackbone Black Steel / Plastic ATX Mid Tower Computer Case
LG DVD Burner - Bulk Black SATA Model GH24NS50


$42.98

1 OCZ Fatal1ty OCZ550FTY 550W ATX12V v2.2 / EPS12V SLI Ready 80 PLUS Certified Modular Active PFC Power Supply
SAMSUNG Spinpoint F3 HD502HJ 500GB 7200 RPM SATA 3.0Gb/s 3.5" Internal Hard Drive -Bare Drive

$15.00 Mail-in Rebate Card
$99.98

1 SAPPHIRE 100283-3L Radeon HD 5770 1GB 128-bit GDDR5 PCI Express 2.0 x16 HDCP Ready CrossFireX Support Video Card
Microsoft Windows 7 Home Premium 64-bit 1-Pack for System Builders

$15.00 Mail-in Rebate Card
$224.98

Subtotal: $603.91

 

[peteysmooth]

One thing I maybe should have mentioned is that the build I've configured contains SC II since it can be combined with a PSU I needed for the build.

Are there parts of that above build that are significant upgrades over what I selected?

Besides a lower cost (it may be hard since I used so many combos already) I'm interested in knowing if some of the parts I've selected are bad ideas or won't work well together. For instance, there seem to be several versions of seemingly identical memory that are different items and even at different prices, like:
http://www.newegg.com/Product/Product.aspx?Item=N82E16820231394
http://www.newegg.com/Product/Product.aspx?Item=N82E16820231396
http://www.newegg.com/Product/Product.aspx?Item=N82E16820231253

This makes me think I'm missing something despite the research I've done as I haven't put together a comp before.