MSI MAG A550BN 550W 80 PLUS Bronze ATX Power Supply

Description

Overview

The MSI MAG A550BN is a compact 550W ATX power supply aimed at mainstream gaming and general desktop systems. It carries an 80 PLUS Bronze efficiency rating (up to ~85%), uses a DC‑DC circuit design and an active PFC to improve voltage stability and efficiency. The unit is non‑modular and fitted with a 120mm low‑noise fan with sleeve bearing. ([storage-asset.msi.com](https://storage-asset.msi.com/datasheet/power-supply/global/MAG-A550BN.pdf))

Key features

• 550W total output with a single +12V rail (45.5A / 546W on the +12V rail).
• 80 PLUS Bronze certification (up to ≈85% efficiency).
• Active PFC and DC‑DC design for stable voltages.
• Industrial protection: OCP, OVP, OPP, OTP and SCP.
• Standard connector set: 24‑pin ATX, 4+4 EPS, 2 × 6+2 PCIe, 5 × SATA, 2 × Molex, 1 × FDD.
• Compact ATX dimensions (140 × 150 × 86 mm) and sleeved cables.

All technical specifications and connector counts are from MSI’s official datasheet. ([storage-asset.msi.com](https://storage-asset.msi.com/datasheet/power-supply/global/MAG-A550BN.pdf))

Who it’s for

Suitable for budget to mid‑range gaming PCs, home/office desktops and builders who need a reliable, compact 550W supply with a conventional (non‑modular) cable layout. It provides a high single‑rail +12V capacity useful for systems with a single graphics card and mainstream CPUs. As with any PSU choice, confirm total system power draw and connector requirements before purchase. ([uk.msi.com](https://uk.msi.com/Power-Supply/MAG-A550BN/Specification))

Warranty & authenticity

MSI lists a 5‑year limited manufacturer warranty for the MAG A550BN; the EAN 4719072870485 corresponds to retailer listings for the same model. Purchase and warranty terms may vary by region and retailer—check the seller and MSI regional support pages for details. ([us-store.msi.com](https://us-store.msi.com/MAG-A550BN?utm_source=openai))