A technician is troubleshooting a desktop computer on the test bench. When the power button is pressed, the power indicator LED illuminates and internal cooling fans spin continuously at maximum speed, but the system displays no output on the monitor, the keyboard caps lock status LED does not respond, and no POST beep codes are produced. The technician removes all RAM modules from the motherboard slots and powers the system on again, but the workstation still remains silent and produces no memory-missing POST beep codes. Which of the following components is most likely defective?
- MotherboardCevap
- BRAM modules
- CGraphics card
- DPower supply unit +12V rail
Cevap
The motherboard is the most likely defective component because a functional motherboard's BIOS/UEFI will recognize missing memory and generate diagnostic POST beep codes or diagnostic LED patterns when powered on without RAM.
Removing all RAM modules is a standard diagnostic step to test system board functionality. If the motherboard and CPU are functional, the BIOS/UEFI will detect the absence of main memory during early POST steps and issue a continuous or patterned beep code (or diagnostic LED code). The lack of any beep code when memory is completely absent confirms that the motherboard is failing to execute the POST routines.
Adım Adım Çözüm
Anahtar Kavram
Motherboard POST Diagnostics and Hardware Isolation