Questions
Q1
How can you to make a RAID within two PCI-e M.2 SSD for GAMING Z170X ?

(1) Install two PCI-E M.2 SSD on motherboard.

(2) Boot into BIOS/Advanced/SATA and RST configuration

(3) Set SATA mode selection to Intel RST Premium, both PCIe storage to RST controlled

(4) Set Boot/storge to UEFI, then Save & Exit BIOS

(5) After reboot, get into BIOS/Advanced/Intel® Raple storage Technology

 (6)Select create RAID Volume

(7) Choose Raid Level for RAID0 or RAID1

(8) Select both device by press SPACE Key, then the [x] will appear (Do not press enter to avoid system crash)

(9) Select Create Volume.

(10) Choose Volume1

(11) Press F10 to save and exit

(12) Create a Win10 installation USB drive

(13) Copy Intel RST driver into Win10 USB drive (32bit or 64bit according to your system)

download link 

32bit https://download.biostar.com.tw/temp/User/f6flpy-x86.zip

64bit https://download.biostar.com.tw/temp/User/f6flpy-x64.zip

(14) Install in UEFI mode (Legacy mode is not support)

(15) During the installation OS will ask you to load RST driver, select the directory with RST driver and continue.