Heres the one I am tweaking out and buying today or tomorrow, prob going to change the SSD and possibly the PSU but the rest stands.
Mother board + CPU combo 249.99
http://us.ncix.com/products/?sku=80960&promoid=1357
Powercooler 7870 - Tahiti LE 210'ish after rebate/shipping
http://www.newegg.com/Product/Product.aspx?Item=N82E168...
And the rest,
PCPartPicker part list:
http://pcpartpicker.com/p/KB1a
Price breakdown by merchant: http://pcpartpicker.com/p/KB1a/by_merchant/
Memory: G.Skill Ripjaws X Series 8GB (2 x 4GB) DDR3-2133 Memory ($59.99 @ Newegg)
Storage: Samsung 840 Series 120GB 2.5" Solid State Disk ($99.49 @ NCIX US)
Case: Thermaltake VL80001W2Z ATX Mid Tower Case ($29.99 @ Newegg)
Power Supply: SeaSonic 520W 80 PLUS Bronze Certified ATX12V / EPS12V Power Supply ($74.98 @ SuperBiiz)
Optical Drive: Lite-On iHAS124-04 DVD/CD Writer ($15.98 @ Outlet PC)
Total: $280.43
(Prices include shipping, taxes, and discounts when available.)
(Generated by PCPartPicker 2013-03-18 17:51 EDT-0400)
Puts me at 740.42 - I don't need a regular HD since I have a 2TB external myself. But a lot of wiggle room in that build.
Also comes with a Bio Shock Infinite + Tomb Raider with the Video Card.
Could also be done with the I5 alternative if that is your preference easily.