BIOS and the BIOS Setup Utility

The Basic Input and Output System (BIOS) is a firmware-based boot program that verifies and initializes the server's input and output hardware. The BIOS prepares the server for operation and allows the server to boot into a known state and function successfully once the operating system takes control of the server. The BIOS is vitally important to the operation of your server, because it contains the necessary server-specific information required for your server to function properly. For example, the BIOS contains information about components installed in the server, the networking environment, and the operating preferences. Without a proper functioning BIOS, your server might not boot or operate properly.

The BIOS has a setup utility stored in the BIOS flash memory. The setup utility reports and stores system information, some of which the utility allows you to configure and customize. The system information is stored in the system’s battery-backed CMOS RAM. If a configuration setting is invalid or if the battery power is removed or sufficiently diminished, the BIOS setting or settings (in the case of a complete loss of battery power) will revert to the factory default. The system BIOS default settings are the optimized settings for your server. Be careful when changing the default settings. An incorrect setting can negatively impact server performance or render the server inoperable and unable to boot. When you customize your BIOS you should record the values, so you can enter them into the BIOS setup utility if the system information becomes corrupted or lost.

• For information about configuring the system BIOS using the BIOS Setup Utility, see How to Configure the System BIOS.

• For screen shots of the BIOS Setup Utility, see BIOS Setup Utility Screens.

• For information about updating the system BIOS, see BIOS and Service Processor Updates.