QNAP TS-451U 4-bay 1U iSCSI NAS, Intel 2.41GHz Dual Core CPU with 1GB RAM, 2.5"/3.5" SATA 6Gb/s, Hot-swappable Intel Celeron Dual Core 2.41GHz, 1GB DDR3L RAM (max 8GB), SATA 6Gb/s, 2 x GbE LAN, Read 224MB/s, Write 222MB/s,, hardware transcoding, HDMI, Virtualization Station (RAM of NAS &gt;= 2GB), Surveillance Station (Max 36 Ch), max 1 UX-800U-RP or UX-1200U-RP expansion unit Manage, share, and back up business data with Real-time Remote Replication (RTRR) ; Enhanced data security with high-performance AES 256-bit encryption and anti-virus Expand the total raw storage capacity up to 128TB with the economical UX-1200U-RP QNAP expansion enclosure ; Use the TS-451U with exclusive QvPC Technology Run multiple Windows/Linux/UNIX/Android-based virtual machines with the Virtualization Station Creatively present your animated content and advertisements with the Signage Station