Dell OptiPlex G1 Service Manual page 133

This appendix, which applies to all Dell OptiPlex G1 Managed PC computer
families, describes the System Setup program, which is used to change the
system configuration information stored in NVRAM on the system board.
To enter the System Setup program, follow these steps:
If you wait too long and the operating system begins to load into memory, let
the system complete the load operation ; then shut down the system and try
again.
NOTE: To ensure an orderly system shutdown, consult the documentation that
accompanied the operating system.
System Setup Program A-1