Dell OptiPlex E1 Reference And Installation Manual page 105

As the system boots, it detects the presence of the new video memory and auto-
matically changes the system configuration information in the System Setup
program.
See Chapter 2, "Using the System Setup Program."
If the video memory total is incorrect, turn off the system, remove the computer
cover, and reseat the video-memory upgrade module in its socket.
For information on using the diagnostics and troubleshooting any problems that
occur, see the chapter titled "Running the Dell Diagnostics" in your Diagnostics
and Troubleshooting Guide .
A 3.0-volt (V) CR2032 coin-cell battery installed on the system board maintains sys-
tem configuration, date, and time information in a special section of memory.
The operating life of the battery can extend up to ten years. The battery may need
replacing if an incorrect time or date is displayed during the boot routine along with a
message such as:
Time-of-day not set — please run SETUP program
or
Invalid configuration information —
please run SETUP program
or
Strike the F1 key to continue,
F2 to run the setup utility
To determine whether the battery needs replacing, reenter the time and date through
the System Setup program and exit the program properly to save the information (see
Chapter 2, "Using the System Setup Program," for instructions). Turn off your system
and disconnect it from AC power for a few hours; then reconnect and turn on your
system. Enter the System Setup program. If the date and time are not correct in the
System Setup program, replace your battery.
You can operate your system without a battery; however, without a battery, the sys-
tem configuration information is erased if the system is turned off or unplugged from
Installing System Board Options 6-11