Beep Codes - Dell OptiPlex 790 Owner's Manual

Power Button
Problem Description A possible system board resource and/or hardware
Troubleshooting
Steps
LED
Power Button
Problem
Description
Troubleshooting
Steps

Beep Codes

The computer can emit a series of beeps during start-up if the display cannot
show errors or problems. These series of beeps, called beep codes, identify
various problems. The delay between each beep is 300 ms, the delay between
74
failure has occurred.
• Clear CMOS.
• Disconnect all internal and external peripherals,
and restart the computer. If the computer boots,
add the peripheral cards back one by one until you
find the bad one.
• If the problem persists, the system board / system
board component is faulty.
Some other failure has occurred.
• Ensure that the display/monitor is plugged into a
discrete graphic card.
• Ensure that all hard drives and optical drive cables
are properly connected to the system board.
• If there is an error message on the screen identifying
a problem with a device ( hard drive), check the
device to make sure it is functioning properly.
• If the operating system is attempting to boot from a
device (optical drive), check system setup to ensure
the boot sequence is correct for the devices installed
on your computer.