Dell OptiPlex E1 Service Manual page 69

This appendix describes the System Setup program for the Dell OptiPlex E1
Managed PC, 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