Intel Core i5-3570K Ivy Bridge 3.4GHz
ASUS GTX680-DC2T-2GD5 GeForce GTX 680 OR
ASUS HD7870-DC2-2GD5-V2 Radeon HD 7870 (I suggest #1, but if you want to save some money #2 will be fine)
ASUS P8Z68-V PRO/GEN3 LGA 1155 Intel Z68 USB 3.0 ATX Intel Motherboard with UEFI BIOS
You didn't specify your RAM, so I took a guess with the motherboard.
Subtotal: CPU + Mobo: $399.98
399.98 + GPU #1: $939.97
399.98 + GPU #2: $659.97
Take my suggestions with a grain of salt, I'm sure other people may be able to find better hardware. =P