Maintenance and Service Guide
Table Of Contents
- Computer features
- Illustrated parts catalog
- Routine care, SATA drive guidelines, and disassembly preparation
- Removal and replacement procedures
- Computer Setup (F10) Utility
- Troubleshooting without diagnostics
- Safety and comfort
- Before you call for technical support
- Helpful hints
- Solving general problems
- Solving power problems
- Solving hard drive problems
- Solving media card reader problems
- Solving display problems
- Solving audio problems
- Solving printer problems
- Solving keyboard and mouse problems
- Solving hardware installation problems
- Solving network problems
- Solving memory problems
- Solving CD-ROM and DVD problems
- Solving USB flash drive problems
- Solving front panel component problems
- Solving Internet access problems
- Solving software problems
- POST error messages
- Password security and resetting CMOS
- Using HP PC Hardware Diagnostics
- Backing up, restoring, and recovering
- Power cord set requirements
- Statement of memory volatility
- Specifications
- Index

Table 7-1 Interpreting POST diagnostic front panel lights and audible codes (continued)
Activity Beeps Possible cause Recommended action
4. Replace the system board.
Red power light ashes six
times, once every second,
followed by a two second pause.
Beeps stop after fth iteration
but lights continue until problem
is solved.
6 Pre-video graphics error. Replace the system board.
Red power light ashes seven
times, once every second,
followed by a two second pause.
Beeps stop after fth iteration
but lights continue until problem
is solved.
7 System board failure (ROM
detected failure prior to
video).
Replace the system board.
Red power light ashes eight
times, once every second,
followed by a two second pause.
Beeps stop after fth iteration
but lights continue until problem
is solved.
8 Invalid ROM based on bad
checksum.
1. Reash the system ROM with the latest BIOS
image.
2. Replace the system board.
Red power light ashes nine
times, once every second,
followed by a two second pause.
Beeps stop after fth iteration
but lights continue until problem
is solved.
9 System powers on but is
unable to boot.
1. Unplug the AC power cord from the computer,
wait 30 seconds, then plug the power cord back
in to the computer.
2. Replace the system board.
System does not power on and
lights are not ashing.
None System unable to power on. Press and hold the power button for less than 4
seconds. If the hard drive light turns white, the
power button is working correctly.
▲ Replace the system board.
OR
Press and hold the power button for less than 4
seconds. If the hard drive light does not turn on
white then:
1. Check that the unit is plugged into a working AC
outlet.
2. Replace the power supply.
Interpreting POST diagnostic front panel lights and audible codes 105