Question ASRock Z370 Killer SLI/ac

- 2 x Ultra M.2 Sockets (M2_1 and M2_2), support M Key type 2230/2242/2260/2280 M.2 SATA3 6.0 Gb/s module and M.2 PCI Express module up to Gen3 x4 (32 Gb/s)
What is the make and model of your SSD that you intend to purchase to drop onto the motherboard? Do you have any other drives populating SATA ports off of the motherboard? I would make sure that the BIOS on your motherboard is flashed to the latest version prior to adding any M.2 drive onto the platform.