With that much budget why not go X79? You can get an i7 4820k or 4930k when they release soon. Also, the quad-SLI Gigabyte UP4 only costs $240.
And you have a budget of $300 for ram? Do you need 32GB of 2133 or something?
And you have a budget of $300 for ram? Do you need 32GB of 2133 or something?