5. Remove or uninstall recently added hardware, software ..........................................  87
6. HP Hardware Diagnostics and Tools ...........................................................................  88
HP PC Hardware Diagnostics (UEFI) .............................................................  88
HP Support Assistant (HPSA) .......................................................................  90
HP BIOS Conguration Utility (BCU) .............................................................  91
HP Image Diagnostic Tool ............................................................................. 91
HP Thermal Monitor .....................................................................................  91
Non HP diagnostics tools .............................................................................  91
7. Status lights, blinking light codes, troubleshooting lights, and POST error 
messages ........................................................................................................................  92
Status lights .................................................................................................. 92
Blinking light codes ......................................................................................  93
POST error messages ...................................................................................  93
Power Good (Troubleshooting) lights ..........................................................  94
Resolve the issue ............................................................................................................................... 95
8. Hard reset .................................................................................................................... 95
9. Soft reset (Default Settings) ....................................................................................... 96
10. Reseat cables and connections ................................................................................  96
11. Test with minimum conguration ............................................................................  97
Essential hardware conguration ................................................................  97
Safe mode ..................................................................................................... 98
12. Test with veried working conguration (hardware and/or operating system) .....  98
13. Replace the system board ........................................................................................  98
Verify solution ...................................................................................................................................  99
Helpful Hints ........................................................................................................................................................  99
At startup ........................................................................................................................................... 99
During operation .............................................................................................................................  100
Consulting with HP Service .............................................................................................................  100
Common issues and possible solutions ............................................................................................................  101
Power-on issues .............................................................................................................................. 101
No Power ....................................................................................................................... 101
Intermittent power-on, shutdown, reboot ................................................................... 103
AC adapter issue ...........................................................................................................  104
Battery not recognized, not charging ........................................................................... 104
Battery discharges too fast ..........................................................................................  106
Burnt smell .................................................................................................................... 107
POST ................................................................................................................................................  107
No video (with power) ................................................................................................... 107
Blinking lights ...............................................................................................................  108
Diagnostics error messages .........................................................................................  109
BIOS password ..............................................................................................................  110
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