Go with a good SSD drive instead of a standard HDD. The difference in performance is absolutely INSANE! With any system, the performance “bottleneck” is almost always in the I/O. This is solved by having a solid SSD. The two best models available right now are the Samsung 840 EVO or the Samsung 840 Pro. The Pro is slightly faster (and slightly more expensive). You'll ask, “Is it worth the extra money to go with an SSD?” My answer, “UNDOUBTEDLY YES!” Below is a link to Amazon.com with the drives:
http://www.amazon.com/Samsung-Electronics-2-5-Inch-Internal-MZ-7TE250BW/dp/B00E3W1726/ref=sr_1_1?s=electronics&ie=UTF8&qid=1394932865&sr=1-1&keywords=Samsung+840
http://www.amazon.com/Samsung-Electronics-2-5-Inch-Solid-MZ-7PD256BW/dp/B009NB8WRU/ref=sr_1_3?s=electronics&ie=UTF8&qid=1394932865&sr=1-3&keywords=Samsung+840
Second: Go with some better/faster RAM. If you're going to overclock the CPU (and I'm sure you will since you're paying extra for the "k" overclock capable CPU), certainly you will OC the RAM as well. Something like this:
http://www.amazon.com/Corsair-Vengeance-Desktop-Memory-CMZ8GX3M2A1866C9/dp/B004CRSM52/ref=sr_1_2?s=electronics&ie=UTF8&qid=1394933466&sr=1-2&keywords=Vengeance+1866
A good quality PSU is important as well. This is a PSU that will give you the wattage you need to power what you have already, plus will give you the option to expand later down the road should you desire. Best to spend a little extra now and not have to spend a lot extra later:
http://www.amazon.com/Corsair-80PLUS-Gold-Certified-Power-Supply/dp/B00EB7UITQ/ref=sr_1_1?s=electronics&ie=UTF8&qid=1394933519&sr=1-1&keywords=rm750+corsair
For solid cooling that will allow you to overclock quite extensively:
http://www.amazon.com/Corsair-Extreme-Performance-Liquid-Cooler/dp/B009ZN03AA/ref=sr_1_1?s=electronics&ie=UTF8&qid=1394933637&sr=1-1&keywords=Corsair+H80
Below, I have enclosed Tom's Guide to building a good gaming PC. It will be useful.
Any questions or comments?
http://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&cad=rja&uact=8&ved=0CCcQFjAA&url=http%3A%2F%2Fwww.tomsguide.com%2Fus%2Fguide-building-gaming-pc%2Cnews-18012.html&ei=yP8kU-uKL6m80gHZg4Bg&usg=AFQjCNG5N9vfJ7VQtxWk2B0n28v_WHfLJw&bvm=bv.62922401,d.dmQ