Originally posted by: bamacre
Without knowing a budget...
EPOX EP-5P945-J 945P P4/Celeron D 1066FSB LGA775 DDR2 ATX Motherboard
$96.75
http://www.zipzoomfly.com/jsp/ProductDetail.jsp?ProductCode=246606
Intel Pentium® D Processor 805 2.66GHz, 533MHz FSB, Socket 775, 2MB Cache, Dual Core Retail
$129.00
http://www.zipzoomfly.com/jsp/ProductDetail.jsp?ProductCode=80849
Corsair VS1GB533D2 1GB DDR2-533 PC2-4200 Value Select Memory Retail
$77.45
http://www.zipzoomfly.com/jsp/ProductDetail.jsp?ProductCode=80098-35
Western Digital Caviar SE16 WD2500KS 250GB Serial ATA II 7200RPM Hard Drive w/16MB Buffer
$91.99
http://www.zipzoomfly.com/jsp/ProductDetail.jsp?ProductCode=101220-12
BFG 3DFuzion GeForce 6200 LE PCI Express 128MB DDR Video Card w/DVI, VGA & S-Video Retail
$44.50
http://www.zipzoomfly.com/jsp/ProductDetail.jsp?ProductCode=326040
Total Price Shipped: $439.69
If you are willing to spend about $120 more, I'd replace the Pentium 805 with a 940...
http://www.zipzoomfly.com/jsp/ProductDetail.jsp?ProductCode=80852
If you want to go single core cpu, I'd recommend going Athlon 64. DDR memory is a little more expensive right now, but a motherboard could be found significantly cheaper.