Identifying an Input/Output FRU Which of the following field-replaceable units (FRUs) is best categorized as an input/output device because it handles both inbound and outbound data?

Introduction / Context:
Field Replaceable Units (FRUs) are components designed for quick swap in service situations. Classifying a part as input/output (I/O) helps technicians allocate interrupts, DMA (where relevant), and drivers during troubleshooting.

Given Data / Assumptions:

• Video boards primarily output display data to a monitor.
• A SCSI host adapter interfaces storage and peripherals, moving data in and out.
• CPUs execute code but are not generally categorized as I/O interfaces.

Concept / Approach:

An I/O FRU is one that bridges the system bus and external/peripheral buses, transferring data bi-directionally. The SCSI host adapter fits this definition: it manages command and data phases with attached devices, performing reads and writes. Video boards are output-centric; CPUs are processors, not I/O interfaces.

Step-by-Step Solution:

Verification / Alternative check:

Driver categories in operating systems list SCSI HBAs under storage controllers (I/O). Service manuals describe replacing HBAs as FRU operations to restore I/O paths.

Why Other Options Are Wrong:

Video boards predominantly output; they are not general I/O bridges. CPUs are compute elements and not classified as FRU I/O devices. “All of the above” and “None of the above” are therefore incorrect.

Common Pitfalls:

Confusing a device that moves data (CPU) with a device that interfaces buses (I/O). The distinguishing feature is external/peripheral bus control.

Final Answer:

SCSI host adapter