If you go with the i5 750 you will still get great performance, plus you can use dual channel RAM instead of tri-channel (two sticks instead of three).
I looked at a parts list of the i5 750, a Gigabyte ATX board, 4GB of G.Skill DDR3, a 500GB WD Black primary drive, a 1TB WD Black data drive, a Corsair PSU, and a XFX 4890 and came us with $1005. that's without a case or OS.