There was some confusion that started with Intel quietly pulled out its latest RSTe drivers for the Intel X99 chipsets, but it turned out that it was listed. However, it is now being said that Intel X99 chipset will only able to work with six SATA slots. Intel did say that up to 10x SATA 3 does work at the time the newer flagship chipset was launched along with the newer LGA 2011-V3 socket Haswell-E processor. However, it won’t work via Intel RSTe (Rapid Storage Technology Enterprise) drivers which will enable you to setup a RAID using all 10 SATA 3 ports. Do note- the last 4 out of 10 occupied SATA 3 ports will be detected by the system, but it will also be using the AHCI drivers and not Intel RSTe drivers. You can use all the first 6 ports in total for RAID via Intel RSTe.
It might not be a big deal for those who require more than 6x SATA for RAID considering most may prefer a discrete RAID card solution. But is this deja vu? Intel X79 had the same issue concerning the SATA ports. It should be noted that back then, all the motherboard manufacturers had to redesign their motherboards, therefore reducing it to 6x ports. We’re not sure if this is what will happen in the motherboards available now.