The HP Smart Array P411 is HP"s PCI Express (PCIe) Serial Attached SCSI (SAS) RAID controller. The low profile, half height card has 8 ports and utilizes DDR2-800 memory. "The P411 is ideal for RAID 0/1, 5, 1+0 & 5+0 and can be upgraded with the 512MB battery-backed write cache (BBWC) or 512MB/1G Flash Backed Write Cache (FBWC) module and Smart Array Advanced via license key for RAID 6 &, 6 +0.