You can use the Oracle System Assistant's Get Updates task to update OS drivers and other firmware components, such as BIOS, HBAs, and expanders, if applicable. You should perform the updates before you install the OS.
The Oracle System Assistant application's Install OS task provides an assisted installation of a supported OS. You supply the OS installation media, and Oracle System Assistant guides you through the installation process. It then fetches the appropriate drivers based on your server hardware configuration. The Install OS task is not available for all server supported operating systems.