Synology RackStation RS4021XS+ NAS, Form Factor (RU) 3U, Capacity 64 GB (16 GB x 4), Drive Bays 16, Max Drive Bays w/ Expansion Unit 40 (RX1217/RX1217RP x 2), Compatibility 3.5" SATA HDD, 2.5" SATA SSD, I/O 4x RJ45 1GbE LAN, 2x RJ45 10GbE LAN, 2x USB-A 3.2 Gen1, 2x Expansion Port, PCIe Expansion: 2 x Gen3 x8 slots (x8 link), PSU 800W, CPU Intel Xeon D-1541 8 Cores 2.1GHz Base, RAM 16GB DDR4 ECC UDIMM 4x Slots. The Synology RS4021XS+ is powered by a 2.1 GHz Intel Xeon D-1541 Eight-Core processor, which will allow you to run multiple functions simultaneously. The built-in 16GB of DDR4 EC