Synology DiskStation 2-Bay (Diskless) Network Attached Storage DS713+ CPU: Dual Core 2.13GHz RAM Size: 1GB DDR3 Internal HDD: 2x 3.5" or 2.5" SATA2 Max Internal Capacity: 8TB (2x 4TB HDD) External HDD Interface: 2x USB 3.0 ports, 1x USB2.0 port, 1x eSATA port Noise Level: 19.2 dB(A) Fan: 1x (92 x 92mm) Fan