The power supply units (PSUs) in the SYS-421GE-TNHR2-LCC system are at the back of the...

In Supermicro’s high-end servers like the SYS-421GE-TNHR2-LCC, PSUs are typically located at the back of the chassis for accessibility and cooling efficiency, a design consistent with DLC rack-scale solutions (e.g., SYS-420GP-TNAR). The mention of a “dummy PSU tray” suggests a placeholder or empty slot, common in modular designs to maintain airflow or allow future expansion. This layout is standard in Supermicro’s DLC systems, where PSUs power both compute and cooling components (e.g., pumps, CDUs). No contradicting evidence exists, and True (A) aligns with Supermicro’s chassis architecture, making it the correct answer.

References: Supermicro chassis design specs, DLC system PSU placement.