Many motherboards offer a "Legacy Mode" option, which makes SATA drives appear to the OS like PATA drives on a standard controller. This "Legacy Mode" eases OS installation by not requiring that a specific driver be loaded during setup, but sacrifices support for some (vendor specific) features of SATA. Legacy Mode often if not always disables some of the boards' PATA or SATA ports, since the standard PATA controller interface supports only four drives. (Often, which ports are disabled is configurable.)