Synology Rack 2U QC3,6GhzCPU/ 4Gb(up to 32)/ RAID0,1,10,5,6/ up to 12 HDDs SATA(3,5' or 2,5')(up to 24 w/ RX1223RP)/ 2xUSB/ 2Gbx1+10Gbx1(+1Expslot)/ iSCSI/ 2xIPcam(up to 40)/ 2xPS/ no rail repl RS2421RP+ (RS2423RP+)