MSI MAG A550BN 550W 80+ BRONZE

MSI MAG A550BN 550W 80 PLUS Bronze

The MSI MAG A550BN is a 550 W ATX power supply designed for desktop gaming and general-purpose PCs. It combines 80 PLUS Bronze efficiency, a single +12 V rail, DC-to-DC circuit design, active PFC and a 120 mm low-noise fan. MSI’s official documentation confirms the supplied EAN 4719072849603 for this exact model.

Key Features

• Power: 550 W
• Efficiency: 80 PLUS Bronze, up to 85%
• Form factor: ATX
• Wiring: Non-modular
• +12 V design: Single rail
• DC-to-DC circuit design
• Active PFC
• Cooling: 120 mm low-noise fan with sleeve bearing
• Color: Black
• Protections: OCP, OVP, OPP, OTP and SCP
• Designed as an entry-level PSU for gaming and desktop PC builds.

Full Specifications

The electrical output figures above come directly from MSI’s published datasheet: the +12 V rail provides 45.5 A / 546 W, while +5 V and +3.3 V provide 20 A each.

Connectors

The MAG A550BN provides the standard connections required for a typical desktop configuration:

• 1 × ATX 24-pin motherboard connector
• 1 × EPS 4+4-pin CPU connector
• 2 × PCIe 6+2-pin graphics-card connectors
• 5 × SATA
• 2 × 4-pin Molex
• 1 × FDD 4-pin connector

Because the PSU is non-modular, all of its cables are permanently attached to the power supply.

Cooling & Internal Design

The PSU uses a 120 mm sleeve-bearing fan designed for relatively quiet operation while providing airflow for heat dissipation. MSI also uses an active PFC circuit and DC-to-DC conversion, with the latter designed to improve output-voltage stability.

Protection Systems

The MAG A550BN includes five protection mechanisms:

• OCP — Over Current Protection
• OVP — Over Voltage Protection
• OPP — Over Power Protection
• OTP — Over Temperature Protection
• SCP — Short Circuit Protection

These are specified by MSI as part of the PSU’s protection system.

Dimensions

150 × 140 × 86 mm (W × D × H) according to MSI’s current specification pages and datasheet.