QNAP TVS-873-16G 16TB (4 x 4TB) Seagate Constellation (Enterpise), AMD R-Series RX-421BD quad-core 2.1 GHz processor, burst up to 3.4 GHz, 16GB DDR4(expandable to 16GB),High-performance 10GbE-enabled business NAS with powerful quad-core AMD R-Series APU