For what it's worth, I've had issues with Intel RST under Windows as well in mixed-mode configs. My boot device is an SSD configured for AHCI and I've a 3 drive

For what it's worth, I've had issues with Intel RST under Windows as well in mixed-mode configs. My boot device is an SSD configured for AHCI and I've a 3 drive RAID array. On a soft reset of my PC, the BIOS won't see the SSD. The completely nonobvious solution? Make the SSD hot swappable. Not a Lenovo PC, either. Been going on for years. Had to do a hard reset every time I had to restart for years before I found a solution to this.