Cache Buffer Size:1 GB Controller Interface Type:Serial Attached SCSI Device Type:Smart Array Controller Width:2.25 Inch Depth:7.5 Inch Height:9.5 Inch It features eight external SAS ports and delivers increased server uptime by providing advanced storage functionality, including online RAID level migration Data compatibility between HP Smart Array Controllers means customers can easily upgrade to future Smart Array Controllers. HP Smart Array Advanced Pack 2.0 firmware makes it easier for customers to protect their data with advanced functionality for this next generation of Smart Array controllers, including features such as RAID 1 ADM