What are you going to be doing? If you're just gaming, go with the Athlon X4 750, it's an amazing budget CPU, and it matches the i5-4670K in performance with a entry-level GPU. If you plan to render large 3D images or do serious scientific/mathematical calculations, or if you're hackintoshing, go the i5-4960K route. Both of those CPUs are seriously overkill.