Understand The Issue; Boot-Up Sequence; Failure Classification - HP ZBook Power G10 Maintenance And Service Manual

1. Understand the issue

It is important to understand the issue that occurred, including related symptoms. It helps to understand
the basic computer boot-up sequence as well as the failure itself.

Boot-up sequence

The computer performs several steps after you press the power button or restart the computer.
It is important to understand where in the boot-up sequence the symptoms occur. The following table
lists the phases of the boot-up sequence and explains the symptoms that may occur in each phase. For
example, a blue screen error (BSOD) often occurs during the performance phase.
Table 6-3 Boot-up sequence and associated failures
Item
Startup
POST (UEFI/BIOS)
Performance
(operating system)

Failure classification

Failure classification is a breakdown of different types of failures and symptoms that could occur during
the boot-up sequence.
Table 6-4 Failure classification by boot-up sequence on page 71
hardware devices on page 72
Table 6-4 Failure classification by boot-up sequence on page 71
sequence.
1. Power-on: Common issues are no power, recycle, or reboot.
2. POST: Common issues are no boot (despite power), light flash, or diagnostics error.
3. Performance: Common issues are Intermittent Loss of Power, Blue Screen, Hang. In many cases,
issues can be identified and associated with particular hardware (for example, display or storage).
Table 6-5 Failure classification by hardware devices on page 72
● Display
● I/O (input/output) devices
70 Chapter 6 Troubleshooting guide
Procedure
After you press the power button, the computer boots after all internal power rails (such as 5 V, 3.3 V) are
stable.
Confirm that power lights are on and fan is spinning.
Common issues: all lights are off; troubleshooting lights are on; computer does not boot; video is absent.
Power-On Self-Test (POST) verifies that hardware components (such as processor, hard drive, memory)
are functional. When POST is complete, the HP logo appears briefly and then disappears.
If there are errors, the computer may exhibit blinking lights and POST error messages, and so on.
Common issues: lights blink; error message appears; system hangs (lock up or freezes)
System boots to operating system, and Windows logo screen appears.
Common issues: hangs, blue screen, distorted video, driver conflict, slow performance, display issue
(dead pixel), I/O issue (no speaker sound), wireless/audio unavailable, noise.
See Analyze the issue on page 73
represent the failure classification for common notebook failures.
table for detailed troubleshooting information.
and Table 6-5 Failure classification by
categorizes failures by the boot-up
categorizes failures by hardware: