@Fernando, @MDM
Thanks for your comments.

On my side, final conclusion:
I don't suceed to have a dual drivers (Intel RST v18 branch handling a RAID 0 array and NVMe Samsung driver NVMe) configuration booting.
I think it is impossible by concept of the Intel RST v18 branch to accept Samsung NVMe and Intel RST drivers coexistence.
The only stable configuration is using the unique driver Intel RST v18 handling all the storage disks (SATA RAID volume and any others storage devices such as NVMe SSDs) with BIOS settings: Intel RST= "on", SATA Mode= "Intel RST Premium with..", RST PCIe Storage Remapping M.2_1 and M.2_2 = "RST Controlled".

I have one other Z390M system but without RAID volume.
It is a Dual drivers system: Intel RST v18 and NVMe Samsung.
This other system is booting well and quite stable and performant. (BIOS settings: SATA Mode= "Intel RST Premium with..", RST PCIe Storage Remapping M.2_1 and M.2_2 = 'Not RST controlled")

@Fernando,

I do agree a better performant configuration should be using the Intel RST driver for the SATA connected RAID0 and the Samsung driver for all tje NVMe SSDs.

1) Unfortunatly I do observe that the current "RST Master v18" configuration does remain "stucky" to the PC:
-> From the current "RST Master v18" configuration I no longer be able to get a bootable configuration using Samsung drivers even without SATA connected RAID0 plugged in.
It does seem V18 traces are stuck somewhere into W10, into sytem SSD and into BIOS.
The simple fact to unplug the SATA connected RAID0 devices, and then try to boot, does fail into an endless boot loop process (circle logo, then BIOS boot menu offered, then circle logo, etc..)!
To get back to have a booting system again, the RAID0 SATA devices must be reconnected.
-> From the current full "RST Master v18" configuration (RAID0 + Samsung SSDs) I tried to downgrade (have disk method) to a "RST v15.9.8.1050" configuration.
Apparently the downgrade RST driver update does seem accepted without any error message and at the completion the process does require a PC Reboot to take effect.
Again, unfortunatly the PC reboot does fail into the endless Reboot loop process.

2) The "RST Master v18" does seem 'immuable' whatever you try to modify: driver version, BIOS setting parameters, RAID0 unplug.

3) It does seem to have seen during the first v18 installation procedure a warning message from Intel that v18 will be "never uninstallable" !
It does seem this experience does confirm this very strange situation.

4) So, at the moment this PC does remain as full "RST Master v18" to be used.

Many thanks for your time to share with me this experience of this PC running in a 'unexpected' way and 'non desirate' "RST master v18" mode.
So, from my point of view once you have upgraded a (NVMe + SATA RAID0) PC to the Intel RST v18 "world", it is like for the live !

@Fernando
I will try your test procedure, but can you confirm me some missing details ?
Do I keep the current BIOS parameters unchanged (SATA mode= RST premium, NVMe= RST controlled) before to start the procedure and during all the procedure ?
I have to disconnect the PC from the net, due to antivirus application.

Step1: I do keep plugged in only the system NVME Samsung 970 and have to wait for 10-15 mn or more to see if the boot loop is infinite or not ?
If finally PC is booting, have to force to replace the Intel RST v18 to NVMe Samsung driver that does require also a reboot PC.
Hope to not be again a endless boot loop time ?
Step2: I have to pick up a SATA drive elsewhere in another PC ... (only for the test purpose), and have also to wait a very long time to see if the system is finally booting ?
If booting, have to force the offered RST driver (but which one ?) to v15.9.8.1050 and then be able to boot ?
Step3: unplug the SATA test drive, reconnect the 2 SATA members of the RAID0 array, and cross the fingers to see if the system is booting well with the mixed drivers configuration ?

As you can see, the critical phase is to pass the booting loop..

Anyway, I let you know the test results.

@Fernando,
Step1 does fail:
As you can see on this screenshot the NVME Samsung driver installation in force (have disk method) does require at the completion a Reboot PC:


So, I have shutdown the PC, then unplug power PC, then replug power PC, then try to reboot.
Unfortunatly the Boot procedure does not work, the Black screen does offer the Round circle for now more than 40 mn !

So, as the PC was not booting, I have modified BIOS setting at the Main Menu with "Intel Rapid Storage Technology: OFF"
This will modify automatically the SATA Mode: AHCI, and observed the both NVMe SSDs (970 and 960) were detected at the BIOS level.


Now, I have to go to Step2.

@Fernando,
As you can see setting to OFF the RST option into BIOS main menu does allow to progress to Step2:


Now, which storage driver I have to force ? Microsoft ?
Thanks to clarify.

@100PIER:
As I already said, LISTEN to what Fernando is saying to you CAREFULLY and do it LITERALLY!
Mais vraiment tu n'écoutes pas (tu ne lis pas non plus...)!

@Fernando,
Yes, I know v15 should installed, but overtaken on which storage driver in place as you can see on the last screenshot of the "AHCI" + "NVMe Samsung" stable configuration ?
AHCI Micosoft ? Which storage item do you propose ? I see not RST choice ..

Zitat von 100PIER im Beitrag #2458

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@Fernando,
Yes, I know v15 should installed, but overtaken on which storage driver in place as you can see on the last screenshot of the "AHCI" + "NVMe Samsung" stable configuration ?
AHCI Micosoft ? Which storage item do you propose ? I see not RST choice ..

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@MDM, @Fernando,

Of course trying to update Microsoft Standard AHCI with Intel RST v15 does not work:


Whatever you do the AHCI stuff is proposed, and if your force by select the IASTORAC of v15 driver folder the installation procedure goes to into an endless research.. without completion and you have to abandon the driver update procedure.
So, no progress !