For a $600 budget, you may want to consider eBay for some parts. I got a i7 3770k for $50, msi z77 mpower for $50, 16Gb Patriot ddr3 1866 for $20, Fractal Design r5 window for $20, Samsung 840 Pro 128Gb for $40. In fact, the only components new were my gtx970 and evga 550 G2. Granted it took some time to piece it together, anxiously waiting on deals, but the results are more than worth it.