Synology RackStation RS4021xs+ (RS4021XS+)

Synology RS4021xs+ RackStation NAS | 3U rackmount | Intel Xeon D-1541, 8 cores @ 2.1 (base) / 2.7 (turbo) GHz | 16 GB DDR4 ECC UDIMM, max. 64 GB (16 GB x 4) | Drive bays/slots: 16 x 3.5″ SATA HDD or 2.5″ SATA SSD | Expansion (optional): up to 40 total drive bays with RX1217 x 2 via InfiniBand (2 expansion ports) | 4x 1GbE RJ-45, 2x 10GbE RJ-45 | 2x USB 3.2 Gen 1 | PCIe: 2 x Gen3 x8 slots (x8 link) | Redundant power supplies | Rail kit sold separately | Synology SATA HDDs: Enterprise HAT5300 family only; Plus HAT3300 not listed | Third-party HDDs: selected listed models from Seagate, Toshiba, Western Digital | Official SATA SSD list: Synology SAT5200 family only | Check the exact model, capacity and firmware for validated drive support