I have set up two AIC SSD 750 drives in CPU-connected PCIe sockets of Gigabyte GA-Z170MX-Gaming 5.
Successful reports of PCIE RAIDs with RST was only on chipset-connected slots.
I expected that the driver of SSD 750 would be updated from Microsoft driver to Intel's IRST driver, but nothing happened.
You checked the controller part in device manager? Drive-part will not be updated.
I found the answere from another post:
The answere was that the driver was installed but I was looking for a wrong entry in the device manager. The drives are listed under Storage Controllers, but not under Disk Drives.