$600? Unless you're building a *nix box you need to set aside around $200 of that for an OS. Say, about $100 for RAM, and another $70 for a HDD (these are insanely low values, I'm just taking it that you'll be buying mid to low performance parts on that budget). After that you'll need a motherboard (keep in mind that you've spent $370 at this point and have $230 remaining for a MoBo, processor, and video card) a cheap motherboard will go for around $50, and processor for another $80. A video card can be cheap, we'll say $30. And this isn't even covering a case/power supply (I'm just presuming you'll take those from a computer you don't use anymore), you'll still need an optical drive of some sort. Say that's another $30 for a CD-ROM(no write capability). That'll leave you $40 for anything else I may have left out. With parts at those prices, you'll have a computer that would have been top of the line about six years ago. A dual core processor would not help with this computer, as the processing power would not be the performance bottleneck (and a motherboard that supports dual-core processors would cost even more).
