Default: Total 10 bays10 front hot-swap 2.5" SATA drive bays Option A: Total 10 bays10 front hot-swap 2.5" PCIe 5.0 NVMe* drive bays Option B: Total 10 bays10 front hot-swap 2.5" SAS* drive bays (*NVMe/SAS support may require additional storage controller and/or cables, please see the optional parts list for details) + 2 M.2 PCIe 3.0 x2 NVMe slots (M-key 2280/22110)