With the release of the X99 chipset came the introduction of DDR4, which is not seeing the same uptake as DDR3 did at launch, though it is still selling well.  Part of this may be the pricing, DDR3 was expensive when it first launched but even stalwart early adopters may balk at the $340 asking price for the Corsair Vengeance LPX 16GB 2800MHz.  The other main reason for the mild reception is the minimal performance gains which DDR4 offers, you can see a slight difference in synthetic benchmarks but when it comes to gameplay the performance increase is minuscule for the price you pay.  If you do have an X99 board then this kit is a good choice for you, not only can you often find similar kits on sale for significantly less that $300, Overclockers Club overclocked these DIMMs to 3200MHz at timings of 16-16-16-30.  Check out their review here.

"Packed full of promise, the latest modules in the Vengeance series of Corsair's DDR4 memory lineup deliver excellent performance when tweaked to get the tightest timings. Out of the box they come with 16-18-18-36 primary timings using just 1.2v to run the modules. By tweaking the applied voltage a little bit you can get the timings much tighter at the rated speed and even when running at my max overclock of 3200MHz. At this speed I was able to run the timings at 15-15-15-28 2T using over 1.4v applied to the modules."

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