67. A technician replaced a failed PBU on a high-end workstation PC. Now, the PC fails to POST and does not stay turned on for more than five seconds. Which of the following power connections was most likely forgotten during installation?
Answer: C
The most likely forgotten power connection is 120V.
When a technician replaces a failed Power Backup Unit (PBU) and the PC fails to POST and shuts down quickly, it suggests a critical power connection issue. The 120V connection is essential for the workstation to operate, and if it was overlooked, the machine would not receive the necessary voltage to power on properly.
A) 5V
The 5V power connection is typically used for powering components such as USB ports and some internal circuits. While important, it is not the primary source of power required for the overall operation of a high-end workstation, making it an unlikely candidate for the forgotten connection in this scenario.
B) 11V
An 11V connection is not a standard voltage used in typical PC power supplies. Most power supplies operate on 3.3V, 5V, 12V, and sometimes 24V. Therefore, this option does not apply to the situation described and can be dismissed as irrelevant.
C) 120V
The 120V connection is crucial because it is the primary voltage supply for most North American electrical systems, providing the necessary power for the entire workstation. If this connection was not made during the installation of the new PBU, the workstation would fail to power on and would shut off quickly due to insufficient power.
D) 220V
The 220V connection is primarily used in regions where higher voltage is standard for household appliances. In North America, the standard is 120V. Unless the workstation was specifically designed to operate in a 220V environment, this option is not applicable and unlikely to be the cause of the failure to POST.
Conclusion
In summary, the most likely forgotten power connection is 120V, as it is critical for the operation of the workstation. Options A, B, and D are either not standard for PC operation or irrelevant to the situation described. Thus, Option C is definitively the correct answer, as it directly relates to the power supply needed for the workstation to function correctly.