This system was build back in Jan 2012. I'm sure pricing/components changed by now but you can use this as a baseline to build a system.
CORSAIR Hydro Series H80 (CWCH80) High Performance Liquid CPU Cooler
GIGABYTE GA-Z68XP-UD3P ATX Intel Motherboard
CORSAIR HX Series HX850 850W Power Supply
EVGA 015-P3-1580-AR GeForce GTX 580
Hard Drive (Secondary Drive)
Hitachi Ultrastar 7K3000 HUS723020ALS640 2 TB 3.5' Internal Hard Drive
Total Cost: $1,842.14 (not including shipping) **This was purchased Jan of 2012**