I have an ancient system (Pentium D 945, 4GB DDR2, GT 630, and 275 watt PSU) and I have narrowed it down to two processors, the i7 3770K or new Haswell i5 4670K. I can get them both bundled with motherboards, the i7 bundle is $275 and the i5 bundle $260. My primary use is gaming and no heavy number crunching. I am leaning heavily towards the i7 right now but if the i5 can do gaming just as well and is more future proof it might be worth the loss in performance.