I'm a proponent of X99. But it's not for everyone.
The most compelling feature of X99 is more PCIe 3.0 lanes, enough to support x16/x16/x8 or x8/x8/x8/x8 multi-GPU configurations. Z97 has enough PCIe 3.0 lanes to support x16, x8/x8, or x8/x4/x4. But regardless of chipset, mATX has 2 slots (x16/x16), uATX has only one slot (x16).
A Z97 uATX can run the same x16 GPU slot as an (hypothetical) X99 uATX, at lower cost.Incidentally, very few GPUs can currently saturate x8 lanes of PCIe 2.0 (half the speed of PCIe 3.0), performance of a x8/x8 vs a x16/x16 benchmarks almost identically either way. So there's little real-world and gaming advantage to be had in X99.
DDR4 is currently no better than high-speed DDR3. DDR4 will not reach it's real potential for a few years and in the meantime DDR3 is being made with the same chips, same speeds, same capacities, and lower cost. Nobody will stop making or selling DDR3 as long as everybody keeps buying DDR3.
A Z97/DDR3 system has basically the same memory speeds and capacities as a X99/DDR4, at lower cost.X99/LGA2011-3 supports a few i7 and Xeon processors with 4 to 8 or more cores, at modest speeds. Z97/LGA1150 supports 2 to 6 cores, at extreme speeds. If you can actually leverage mega-multithreading madness then cores matter (but lack of multi-GPU parallel processing power will be a huge productivity bottleneck). If you want a general-purpose or leet extreme gaming rig then 4-6 cores (and HyperThreading) is already overkill and the real performance bottleneck is raw processor speed. Most games lean on the GPU(s) and make use of, at most, 2-4 (maybe 6) main processor cores - not just the games which are newest and heaviest today, but also for the next several years.
A Z97/i7-4790K system is faster gaming than any X99 system, at lower cost.Another compelling option many enthusiasts forget about - AMD.
An AMD RD990FX+SB950/DDR3/FX-9590 system compares favourably vs an Intel Z97/DDR3/i7-4790K, at generally lower cost.
A higher-end AMD APU system (such as an A88X/DDR3/A10-7850K) would be disdained by extreme gamers but is nonetheless overkill enough for general use and moderate gaming (or even heavy gaming, with a mighty GPU card), at much lower costs.
Things will likely change in future years, when newer generations of LGA2011-3 processors and DDR4 become available. For now, you could almost build two complete top-tier Z97 platforms at the same price as a single top-tier X99 platform, and still the X99 would be outperformed by either one.
"All opinions are not equal. Some are a very great deal more robust, sophisticated and well supported in logic and argument than others." - Douglas Adams
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