SYNOLOGY DS1621+ 6BAYS 8o RAM. BUNDLE + 6 DISCS 4TB WD Main features: AMD Ryzen Embedded V1500B Processor (Quad-Core 2.2 GHz - 8 Threads) 4 GB DDR4 ECC SO-DIMM (1 x 4 GB - 2 Slots - 32 GB max.) (D4ES01-4G / D4ES01-8G / D4ECSO-2666-16G) 4 x 1 GbE LAN (with aggregation or failover) PCI-Express 3.0 x8 slot operating at x4 that can accommodate a 10GbE network interface card: E10G18-T2, E10G18-T1, E10G17- F2 6 SATA 6 Gbit/s 2.5"/3.5" bays and two M.2 2280 PCIe 3.0 x4 slots for SSD cache (Expansion possible) with two DX517) External file system: Btrfs, ext4, ext3, FAT, NTFS, HFS+, exFAT (via additional license purchase) Support for collaboration with Synology Chat instant messaging service, Synology Editor Synology Office online and Synology Calendar scheduling assistant Synology Chat: 1500 users max. Synology MailPlus / MailPlus Server: 150 concurrent users (5 free accounts) Synology Office: 1800 users maximum Maximum connections: 30 VPN protocols supported Network protocols: SMB1 (CIFS), SMB2, SMB3, NFSv3, NFSv4, NFSv4.1 , NFS Kerberized sessions, iSCSI, HTTP, HTTPs, FTP, SNMP, LDAP, CalDAV Virtualization: VMware vSphere 6.5, Microsoft Hyper-V, Citrix, OpenStack Virtual Machine Manager: 8 machines recommended (1 license provided) Security: Firewall, shared folder encryption, SMB encryption, FTP over SSL/TLS, SFTP, rsync over SSH, automatic connection blocking, Let's Encrypt support, HTTPS (customizable cipher suite)