The JMicron JMB393 is a SATA II Port Multiplier chip that expands one port into five with RAID support. It uses JMicron’s proven multi-port SATA PHY technology and proprietary storage processor to deliver efficient RAID performance. With simple configuration, it can function as a port multiplier, performance booster, or data protector. Supporting eSATA compliance, the JMB393 offloads processing from the main CPU, making it ideal for both internal and external storage solutions where data protection and performance aggregation are essential.