Owners Manual
Troubleshooting Your Computer
You can troubleshoot your computer using indicators like Diagnostic Lights, Beep Codes, and Error Messages during the operation of the
computer.
Topics:
• Diagnostic LEDs
• Error Messages
Diagnostic LEDs
NOTE: The diagnostic LEDs only serve as an indicator of the progress through the Power-On Self Test (POST) process.
These LEDs do not indicate the problem that caused the POST routine to stop.
The diagnostic LEDs are located on the front of the chassis next to the power button. These diagnostic LEDs are only active and visible
during the POST process. Once the operating system starts to load, they turn off and are no longer visible.
Each LED has two possible states of OFF or ON. The most significant bit is labeled with the number 1, and the other three are labeled 2, 3,
and 4, as you go down or across the LED stack. The normal operating condition after POST is for all four LEDs to be ON and then turn off
as the BIOS hands control over to the operating system.
NOTE: The diagnostic lights will blink when the power button is amber or off, and will not blink when it is white.
Table 13. POST Diagnostic LED Patterns
Diagnostic LEDs
• The computer is either
turned off or is not receiving
power
• The computer is booted and
operating normally.
• If the computer is turned off , connect the AC power-supply
and power-on the computer.
PCI device configuration activity
is in progress or PCI device
failure was detected.
• Remove all peripheral cards from the PCI and PCI-E slots and
reboot the computer. If the computer boots, add the
peripheral cards back one by one until you find the bad one.
A possible processor failure has
occurred.
• Re-seat the processor.
Memory modules are detected,
but a memory power failure has
occurred.
• If two or more memory modules are installed, remove the
modules, then reinstall one module and re-start the computer.
If the computer starts normally, continue to install additional
memory modules (one at a time) until you have identified a
faulty module or reinstalled all modules without error. If only
one memory module is installed, try moving it to a different
DIMM connector and re-start the computer.
• If available, install verified working memory of the same type
into your computer.
A possible graphics card failure
has occurred.
• Ensure that the display/monitor is plugged into a discrete
graphic card.
• Re-seat any installed graphics cards.
• If available, install a working graphics card into your computer.
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Troubleshooting Your Computer 47