Update of the start post
Changelog:

• new:
  • "pure" 64bit Intel RSTe SATA+sSATA AHCI & RAID drivers v6.2.0.1238 WHQL for Win8-10 x64 dated 09/18/2019
  • Intel RSTe Storage Drivers & Software Set v6.2.0.1239 for Win7-10 x64 dated 09/24/2019
    Note: This Set contains the above mentioned "pure" Intel RSTe AHCI and RAID drivers v6.2.0.1238 for Win8-10, but additionally
    • 64bit Intel RSTe SATA/sSATA AHCI and RAID drivers v5.6.0.1006 dated 01/25/2019 for Win7 x64,
    • 64bit Intel RSTe VROC drivers v6.2.0.1234 dated 09/10/2019 for Win8-10 and v5.6.0.1016 dated 05/07/2019 for Win7 x64,
    • 64bit Intel RSTe NVMe drivers v6.2.0.1234 dated 09/10/2019 for Win8-10 and v5.6.0.1006 dated 01/25/2019 for Win7 x64.
    
    They all are WHQL certified and designed for Intel C600/C600+/C220/C220+ Series Chipset systems like X79, X99 and X299. Only Windows Operating Systems from Win7 up to Win10 with a 64bit architecture are supported.
• Thanks to westlake for the source package.

@kathampy:
To whom did you address your question?
Since I neither have a mainboard with an X299 chipset nor an Intel Optane SSD, I cannot help you.

@kathampy:
You have to find out yourself, which specific NVMe driver is the best for your individual system and preferences.
It is no problem to return to a previously used storage driver, if you run the Device Manager, right-click onto the related Storage Controller and choose the options "Update driver" > "Browse my computer..." > "Let me pick...".
Unless you have unchecked the related option, you will see a list of all "compatible devices". Now you can simply click onto the listed Controller name given by the previously installed storage driver (e.g. "Standard Nvm Express Controller") and you will get it working after the reboot.
What do you mean with "Client NVMe driver"?

@kathampy:
Is an Intel Optane SSD or an Intel Optane Memory (or even both) required for the usage of the "Intel(R) Optane Memory and Storage Management application?

@kathampy:
After having read your statement, that Intel Optane Storage/Memory hardware may not be required for the usage of the "Intel"(R) Optane Memory and Storage Management" application, I have tried to use it.
Unfortunately I got finally this picture:

Meanwhile I know the reason: I have an Intel Z170 chipset system with a Skylake CPU, but the usage of the Intel Optane Memory features require a system with a modern Intel chipset from 200-Series up resp. with a modern Intel CPU from the KabyLake series up.

@kathampy:
Yes, I had no problem to update the Intel RAID BIOS modules to v17.8.0.4438, to create from within the BIOS a RAID0 array consisting of 2x250 GB Samsung 960 EVO SSDs, to do fresh install of Win10 x64 Pro v20H1 onto it and to get the Intel RST Drivers & Software Set v17.7.0.1006 properly working. Even the installation of the "Intel(R) Optane Memory and Storage Management" App worked fine, but I couldn't use it.