A Smart Array P812 Pci-Express x 8 24-Port SAS Raid controller with a 1GB flash backed write cache. Includes the following items: Smart Array P812 controller board - PCIe x8 SAS controller - Has two internal x4 mini-SAS port and four external x4 mini-SAS port - Supports up to 108 drives across 24 ports. Flash backed write cache (FBWC) super capacitor module assembly - Includes capacitor with holder and retainer. 1GB flash backed write cache (FBWC) memory module - Plugs into the system I/O board.