STION NO: 7A technician is selecting a power supply for a new computer.

USB devices rely on 5V output from the power supply, so the amperage rating at 5V is critical to ensure enough power is available for multiple USB devices. A modular connector count affects cable management, while a 20+4 power connector is standard for motherboard connections. Energy efficiency impacts overall power usage but is not specific to the needs of USB devices. This matches CompTIA A+ Core 1 objectives regarding power supply selection based on device requirements.