Cooler Master MPW-4001-ACAAN1

Overview

The Cooler Master MPW-4001-ACAAN1 is a 400 W ATX power supply designed to provide stable and reliable power for everyday PC builds. Delivering its full 400 W output through a single +12 V rail, it ensures consistent current for entry-level graphics cards and modern processors, preventing unexpected shutdowns and voltage drops. With 75 percent efficiency, it minimizes wasted energy and heat, while its 120 mm fan with intelligent speed control maintains quiet cooling even in ambient temperatures up to 104 °F (40 °C).

Key features

• Single +12 V rail delivering continuous 400 W output for steady power to critical components
• 75 percent efficiency reduces energy waste and lowers operating temperatures
• Operates reliably in warm environments up to 104 °F (40 °C), suitable for cases with limited airflow
• Non-modular design with fully sleeved, pre-attached cables simplifies installation for all skill levels
• Six SATA connectors support multiple SSDs and hard drives, while PCIe and peripheral connectors cover graphics cards and legacy devices
• 120 mm fan with smart speed control balances effective cooling and low noise output
• Built-in over-voltage and short-circuit protection safeguards your system from electrical faults
• Compact ATX form factor fits easily into most mid tower and mini tower PC cases

Key specs

• Power output: 400 W continuous
• +12 V rail: single rail delivering full 400 W
• Efficiency: 75 percent
• Operating temperature: up to 104 °F (40 °C)
• Cooling: 120 mm fan with intelligent speed control
• Cable type: non-modular, fully sleeved and pre-attached
• Connectors: six SATA, one PCIe, multiple peripheral
• Form factor: ATX

Connectivity and compatibility

This power supply offers a versatile range of connectors to support a variety of PC components. The six SATA connectors allow you to connect multiple storage drives, while the PCIe connector is ready for a dedicated graphics card. Additional peripheral connectors provide power for fans and older hardware, making it a flexible choice for upgrading or building systems with mixed components.

Installation and setup

The non-modular design with fully sleeved, pre-attached cables removes the guesswork from installation, especially for first-time builders. The compact ATX size ensures it fits smoothly into most standard PC cases, including mid tower and mini tower models. This setup helps speed up assembly and reduces cable clutter, contributing to better airflow and easier maintenance.

Ideal uses and environments

This power supply is well suited to budget-conscious users refreshing older family PCs, outfitting office workstations, or assembling entry-level gaming rigs. Its ability to operate in warmer conditions and deliver stable power makes it a practical choice for systems in rooms without advanced cooling or for builds that prioritize reliability over extra features.

Orders are processed within 2 business days, which includes verification, packing, and dispatch. Shipping costs are calculated at checkout based on destination, total weight, and selected speed. Free shipping applies to carts over $100 (excluding heavyweight items). All available options and final pricing are clearly shown before payment so you can choose the service that best fits your needs.

Deliveries are handled by major carriers such as USPS, UPS, and FedEx. Estimated delivery times are displayed at checkout and may vary depending on service level and location. Please note that these are estimates and can be affected by weather, holidays, or carrier volume. Once your order ships, you’ll receive a tracking number for real-time updates from pickup to final delivery.

Providing an accurate shipping address helps prevent delays, and changes may be limited once the order has been dispatched. P.O. boxes are supported only when permitted by the selected carrier. Packaging and handoff are optimized to protect items during transit, though oversized or high-weight products may require special handling. All shipping methods and any related constraints are clearly shown during checkout.

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Returns are accepted within 30 days of delivery. Items must be unused, in the same condition received, with tags, manuals, accessories, and original, unaltered packaging. Any item kept will be deducted from the refund. Start a return by sending us an email. Items sent back without approval may be refused or returned to the sender.

Some items are not returnable: opened TVs/combos/monitors 37″+, opened computers or software, electronic downloads, opened consumables (film, paper, bulbs, media, ink), custom or modified computers, special-order or “nonreturnable” items, submerged underwater gear, and opened educational media.

After inspection, refunds are issued to the original payment method; allow 5–7 business days for the credit to post. Shipping, handling, customs duties, and import taxes are nonrefundable. If an item is used, incomplete, or not in original condition, a 30% restocking fee may apply. Direct exchanges are not offered; purchase the replacement and return the original for a refund.

We act solely as a reseller. Any product warranty is provided and administered by the manufacturer, not by our store. That means eligibility, coverage, and outcomes are determined by the manufacturer’s policy for each brand and model. Before purchasing, we recommend reviewing the warranty terms on the manufacturer’s website or in the product documentation to confirm what is covered and for how long.

If you need warranty service, please file the claim directly with the manufacturer. They may require proof of purchase, the product serial number, original packaging, photos, or basic troubleshooting. Some brands ask you to register the product or obtain a case number before shipping it for repair or replacement. We don’t submit or approve claims, but we can point you to the correct support links and contact details.

Keep your invoice and packaging in a safe place, and report any functional issues to the manufacturer as soon as they appear. If you’re unsure whether a problem is covered, the manufacturer’s support team can confirm next steps and timelines. While we cannot intervene in decisions or outcomes, we’re happy to provide purchase documentation or guidance so you can move through the warranty process smoothly.

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