- Intel i5-2400. Though not as popular as the 2500k, it's still got more than enough power. $189.99
- ASRock H61. ASRock normally makes pretty nice stuff, this board should be no exception. $69.99
- 4GB Crucial RAM basic budget stuff. $18.99
- Antec EarthWatts 430w power supply. A great power supply by a great brand, and plenty of power for this build. $59.99
- HIS Radeon 6870. Plenty of power at a great price. Perfect for this build. $159.99
- Hitachi 500GB HDD. Hard drives are currently much more expensive than normal due to flooding in Thailand. This will be your best bet. $79.99
- Lite On CD/DVD burner. Just a cheap, simple, OEM drive, not much to say here. $17.99
- Apex 393 case. The most basic of cases, but it'll have to do. $19.99
Now, you're thinking "But wait, that's over $600!" They key here is that the Radeon 6870 has a $20 mail in rebate, bringing you back below $600.
As you can see here, it's completely possible to build a decent gaming computer for under $600. With prices going down and technology getting better and better, this will become even more the case in the near future.