Ok, so I finished my LA Methods final far earlier then expected.
AMD Athlon X2 3600+ 1.9Ghz - 59
Abit KN9S nForce 550 - 79.99
Supertalent 667Mhz C5 DDR2 RAM - 84.99 (Promo code available)
XFX 7600GT 256MB - 119.99 (-20 MIR)
Arctic Cooling Freezer 64 Pro - 29.99
Cooler Master Elite ATX Case - 39.99 (-10 MIR)
Samsung Spinpoint 200GB 7200Rpm SATA HDD - 55.99
Lite-on DVD-RW SATA Optical Drive - 25.99
Hiper 480W PSU - 49.99
Grand Total: $545.92 dollars + Shipping - 30 Dollars in Mail-In Rebate's. And, if you're cool you can get another 15 dollars off of that with a promo code on the ram.
You can easily overclock that processor to 2.5Ghz with no worries, you have a brand name powersupply and case, solid graphics and a great motherboard, quiet effective hard drive, and you've gotten a SATA DVD burner to boot. And, you're under budget! You can spend another 55 dollars elsewhere, maybe in the PSU, or probably a bigger hard disk, whatever. If that were a C2D build with a similar quality motherboard and processor, you'd be paying another 100 dollars easily, probably more. And if you have a case, optical drives, hard disks, etc to bring over to the new build - that's even MORE savings.