Troubleshooting Guide

A–6 www.hp.com Troubleshooting Guide
POST Error Messages
Red Power LED
flashes two times,
once every second,
followed by a
two-second pause.
The Power LED will
continue flashing
until the problem is
resolved.
None Processor
thermal
protection
activated:
A fan may be
blocked or not
turning.
OR
The
heatsink/fan
assembly is
not properly
attached to
the processor.
1. Ensure that the computer air vents
are not blocked and the processor
cooling fan is running. Leave a
4-inch (10.2-cm) clearance at the
back of the system unit and above
the monitor to permit the required
airflow.
2. Open hood, press power button,
and see if the processor fan spins. If
the processor fan is not spinning,
make sure the fan's cable is
plugged onto the system board
header. Ensure the fan is
fully/properly seated or installed.
3. If fan is plugged in and seated
properly, but is not spinning, then
replace processor fan.
4. Reseat processor heatsink and
verify that the fan assembly is
properly attached.
5. Contact an authorized reseller or
service provider.
Red Power LED
flashes three times,
once every second,
followed by a
two-second pause.
The Power LED will
continue flashing
until the problem is
resolved.
None Processor not
installed (not
an indicator of
bad
processor).
1. Check to see that the processor is
present.
2. Reseat the processor.
Diagnostic Front Panel LEDs and Audible Codes (Continued)
Activity Beeps
Possible
Cause Recommended Action