I'd go R31Nismoid's deal of box, that's dirt cheap for what it is.
I just bought a dual core 2.93 (E7500) with 4 g of ram, 9800GT video card, 1tb hdd etc for about $700, and it seems to play my games quite nicely. I usually buy one of something like this per year, and retire the older box as some form of movie server, web server, etc.