Dell PowerEdge Expandable RAID Controller 4 Dual Channel RAID controller, PERC4/DC (PREC 4/DC) is a high-performance, intelligent peripheral component interconnect (PCI)-to-small computer system interface (SCSI) host adapter with RAID control capabilities. It provides reliability, high performance, fault-tolerant disk subsystem management, and is an ideal RAID solution for internal storage in Dell's workgroup, departmental, and enterprise systems. The RAID controller offers a cost-effective way to implement RAID in a server. A great radi controller that can be installed in most of the DELL PowerEdge servers.