There is no RAID support for NVMe drives with Z97 and X99 chipsets, only OS (Software) RAID. These chipsets do not have the PCIe/SATA remapping technology required for iRST to support NVMe devices.
Some systems using the Intel® Z170 Chipset and Intel® Rapid Storage Technology are capable of using RAID with PCIe* NVMe* SSDs. We would recommend you to check with the Computer Manufacturer Support before purchasing to confirm if a specific system supports this. Some Z170 systems may not have the device mapping and BIOS features required to create a bootable RAID volume.
This is the first time I have ever heard about RAID support for NVMe SSD.
I have particular Z170 motherboards from GIGABYTE and ASUS in mind, and will certainly check their NVMe support.
Will it be that you need to put both SSD 750s in PCIe sockets connected to the chipset and not to CPU?
All Intel® SSD 750 Series are PCIe* NVMe* devices, so they will always be connected using PCIe*.
Some new motherboards allow the PCIe/SATA remapping, required for iRST to handle RAID with these drives, however, you would have to contact the Motherboard manufacturer to confirm if this is enabled/supported for a specific motherboard model. You may also be able to find external websites with information from other users about their experiences with this configuration.
Thanks again for you comments.
What I meant was that some PCIe sockets are connected directly to CPU, whereas others are hunging from the chipset. From your first comment about Z170 being capable of remapping PCIe to SATA, I took it that for SSD 750 to be recognized for BIOS RAID both of them will need to be put in PCIe sockets that are connected to Z170. It looks obvious but I wanted to make sure.
I have since found two reports, one using ASUS Z170 Delux and another ASRock Z170 Extreme7+, that demonstrate BIOS RAID using SSD 750. However, if there is any microATX board, I would prefer that.
I am glad that we were able to clarify your concerns regarding RAID and Intel® SSD 750 Series.
At thist point, we advise you to check with the Motherboard Manufacturers if they have any motherboards that meet your requirements, including the form factor.