What is a server chassis?

• A. The main PCB that interconnects CPU(s), memory, storage, NICs, and expansion cards via buses and chipsets.
• B. The physical enclosure that houses the server's components and provides mounting, airflow channels, and physical security.
• C. The central Processing Unit that executes instructions.
• D. The CPU heatsink and fan assembly for cooling.

Answer: (B)

The server chassis is the physical enclosure that houses the server’s components and provides mounting, airflow channels, and physical security. It’s the metal box that fits into a rack, giving you the frame and space to hold the motherboard, CPUs, memory, storage, and expansion cards, while also shaping how cooling air flows through the system. The chassis is designed with mounting rails, drive bays, and often hot-swappable power supplies, all arranged to optimize cooling and serviceability.

This isn’t the same as the motherboard (the main PCB that interconnects CPU, memory, storage, NICs, and expansion cards) or the CPU itself, or the CPU’s heatsink and fan. Those are internal components inside the enclosure. Understanding this distinction helps you see why the chassis matters for size (form factor like 1U or 2U), airflow management, and physical security in a data center.