Device drivers are the software interfaces that talk directly to the physical raid hardware and are required for the hardware in the computer to communicate with the operating system. A "driver" is the name given to the software interface that allows the operating system to communicate with the hardware. If the raid device is not performing as expected then it is likely that the driver is not working correctly. A PCI\VEN Code can be split into pieces that correspond to manufacturer of that hardware. The first part, the "PCI\VEN_", is specific to the hardware manufacturer, Silicon Image® has the PCI\VEN code of "PCI\VEN_1095". The "&DEV_" part of the code relates to the category of the hardware, in this case the "DEV_0680" category is "RAID" hardware. A list of compatible device driver software for the Silicon Image® PCI0680 Ultra ATA 133 Host device is shown below.