10 Best Fanless Computer Power Supplies for Quiet, Efficient PCs in 2026

The best fanless computer power supplies reduce noise without sacrificing electrical efficiency, modularity, or compatibility. This roundup compares fully passive units, compact DC power solutions, and semi-passive models that stop their fans during light workloads.

Whether you are building a silent home theater PC, a small-form-factor system, or a powerful workstation, focus on wattage, connectors, physical format, efficiency, and cooling requirements—not just the word “fanless.”

Best 10 Fanless Computer Power Supplies Picks for 2026

Premium Silent Power – Seasonic PRIME TX-700 Fanless

For builders seeking fanless computer power supplies, the Seasonic PRIME TX-700 combines a fully modular ATX design with 700W of output and 80+ Titanium efficiency. Its fanless design is suited to systems where minimizing PSU noise is a priority.

Best For: Quiet, efficiency-focused ATX desktop and workstation builds.

Pros:

• Fully modular cabling simplifies installation and cable management.
• 80+ Titanium efficiency supports reduced energy waste.
• 700W capacity fits many mainstream and performance-oriented desktop systems.
• Rated for operation up to 50°C.

Cons:

• Its ATX form factor is less suitable for compact SFX or 1U systems.
• 700W may be limiting for the most power-hungry component configurations.

The PRIME TX-700 is a strong choice when silent operation, premium efficiency, and modular connectivity matter more than compact dimensions or extreme wattage.

Compact DC Power – Yosoo 300W 24-Pin Module

This Yosoo module is a compact alternative among fanless computer power supplies, delivering 300W from a 12V input for mini-ITX, 1U, HTPC, POS, and similar systems. Its external design and included cables support straightforward installations.

Best For: Mini computers, HTPCs, POS systems, and other 12V-based compact builds.

Pros:

• Over 85% efficiency helps reduce wasted energy.
• Includes a 24-pin ATX cable plus Connect, AUX, and SATA cabling.
• Over-current and short-circuit protection add a layer of system protection.
• Industrial solid capacitors are rated for high-temperature operation.

Cons:

• 300W output is intended for lower-power systems rather than demanding gaming PCs.
• Requires a compatible 12V input environment and is not a conventional internal ATX PSU.
• The supplied notes do not identify a formal fanless operating mode.

Choose this module for compact, specialized systems where a 12V power source and included ATX-style connections are more important than traditional PSU enclosure convenience.

High-Wattage Quiet Power – Phanteks AMP GH 1200W

The Phanteks AMP GH is a high-capacity option for fanless computer power supplies, offering 1200W, an ATX 3.1 platform, and PCIe 5.1 support. Its temperature- and output-based 0RPM mode allows silent operation when cooling demand is low.

Best For: High-end gaming PCs and workstations using modern, power-hungry graphics hardware.

Pros:

• 1200W capacity provides substantial headroom for demanding systems.
• ATX 3.1 and PCIe 5.1 support include a 12V-2×6 GPU cable rated up to 600W.
• 80Plus Platinum efficiency and 0RPM fan mode support quiet operation.
• Fully modular individual cables include cable combs for cleaner routing.

Cons:

• The fanless mode is described as 0RPM operation, not necessarily permanent fanless operation under high loads.
• Its ATX format and high capacity may be excessive for compact or low-power builds.
• The supplied warranty description is one year.

With modern GPU connectivity and substantial output, the AMP GH suits performance builders who want quiet low-load operation without giving up the cooling support of a temperature-controlled fan.

Small-Form-Factor Silence – Lian Li SP850P Platinum SFX

The Lian Li SP850P is a compact SFX choice among fanless computer power supplies, providing 850W and 80 Plus Platinum efficiency. Its fanless mode activates at loads of 40% or less, while the included bracket supports installation in compatible ATX cases.

Best For: Compact gaming and creator systems that need high wattage in an SFX format.

Pros:

• 850W output delivers strong capacity for an SFX power supply.
• Fanless mode at 40% load or below supports quiet operation.
• Included SFX-to-ATX bracket expands case compatibility.
• Flexible cables and 100% Japanese 105°C-rated capacitors support easier building and durability.

Cons:

• The fan can engage above the stated 40% load threshold.
• SFX cabling and dimensions may require more planning in larger ATX cases.
• Its white finish may not suit every build theme.

The SP850P is a practical fit for compact systems needing more power than typical small-form-factor units provide, especially when quiet low-load behavior and flexible installation are priorities.

Best Compact Pick – Mini ITX 350W Silent Fanless DC PSU

For compact builds, this Mini ITX DC power supply keeps your system quiet without taking up much room. Its fanless design, stated 350W output, and 85%+ efficiency make it a practical option when comparing fanless computer power supplies for a small-form-factor PC.

Best For: Mini ITX PCs, home theater systems, and quiet office builds with compatible DC input requirements.

Pros:

• Ultra-compact Mini ITX form factor for space-constrained builds.
• Fanless operation produces no power-supply fan noise.
• Includes overvoltage and short-circuit protection.
• Coated PCBA is designed for durability during continuous operation from 0°C to 40°C.

Cons:

• Its compact DC design is intended for compatible Mini ITX systems rather than standard ATX builds.
• Supplied specifications also list 200W output, so buyers should verify the required rating before installation.
• Temperature support is limited to the stated 0°C–40°C range.

This is the most space-conscious and truly fanless option in the roundup, but compatibility and the output-rating discrepancy deserve careful checking before purchase.

Best High-Power Choice – Thermaltake Toughpower GT 850W ATX PSU

The Thermaltake Toughpower GT provides 850W for demanding gaming and workstation systems. It is not a fully fanless power supply, but Smart Zero Fan technology can minimize fan noise during low-load operation, making it relevant for shoppers comparing fanless computer power supplies and semi-passive alternatives.

Best For: High-end gaming PCs and workstations using modern GPUs and requiring ATX 3.1 and PCIe 5.1 support.

Pros:

• 850W output with a high-amperage single +12V rail.
• 80 PLUS Gold efficiency rated up to 90%.
• Native PCIe 12V-2×6 connector for modern graphics cards.
• Fully modular design with flat cables for easier cable management.

Cons:

• Uses one fan, so it is not completely fanless.
• Its ATX form factor is unsuitable for ultra-compact Mini ITX enclosures without ATX PSU support.
• Smart Zero Fan reduces noise at low loads but does not guarantee silent operation under heavier loads.

This is a capable, future-focused ATX option for powerful systems, especially where modern GPU connectors matter more than completely passive cooling.

Best Quiet Gaming Option – be quiet! Pure Power 13 M 750W

The be quiet! Pure Power 13 M combines 750W of power with semi-passive cooling, so its fan turns off at low loads and starts only when needed. While it is not fully fanless, this approach makes it a strong quiet-operation alternative among fanless computer power supplies for gaming and media creation systems.

Best For: Quiet gaming, overclocked GPU, and media creation PCs needing modern graphics-card support.

Pros:

• 80 PLUS Gold and Cybenetics Platinum efficiency certifications.
• Semi-passive zero-RPM cooling at low loads.
• ATX 3.1 support with native 12V-2×6 and four PCIe 6+2-pin connectors.
• Fully modular design, LLC topology, and a 10-year warranty.

Cons:

• It includes a 12 cm fan, so operation is not completely fanless.
• Its ATX form factor is intended for standard PC cases rather than the smallest Mini ITX enclosures.
• Fanless operation is limited to lower-load conditions.

Choose this model when near-silent operation and modern GPU compatibility are priorities, but select a truly fanless DC unit instead if zero fan noise under all loads is essential.

High-Wattage ATX Pick – CORSAIR RM1000e 1000W

CORSAIR RM1000e (2025) ATX 3.1 PCIe 5.1 Ready 1000W Power Supply – Black | Native 12V-2x6 Cable Included, Low-Noise, Fully Modular, Cybenetics Gold, Modern Standby Mode, NA

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The CORSAIR RM1000e is a high-capacity ATX option for builds that need substantial power, though it is not a truly fanless computer power supply. Its 120mm rifle-bearing fan uses a calculated curve to keep noise down, while the fully modular design helps reduce unused cabling.

Best For: High-performance desktop builds needing 1000W, ATX 3.1 compliance, and a native 12V-2×6 cable.

Pros:

• 1000W output with ATX 3.1 and PCIe 5.1 support.
• Fully modular cables and included native 12V-2×6 connection.
• 105°C-rated capacitors and a seven-year manufacturer warranty.

Cons:

• Uses a 120mm fan rather than fanless cooling.
• Its 1000W capacity may be unnecessary for modest systems.

The RM1000e emphasizes modern GPU compatibility and quiet operation rather than zero-fan operation. It is a sensible choice when extra wattage and current-generation connectivity matter more than a completely fanless design.

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Fanless-Mode Choice – Phanteks AMP GH 850W

Phanteks AMP GH 850W Gold Power Supply, ATX 3.1 and PCIe 5.1 Platform, Fully Modular Individual Cables, Silent Fanless Mode, White

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The Phanteks AMP GH is the closest match here for shoppers seeking fanless computer power supplies, thanks to its temperature- and output-based 0RPM fan mode. It combines 850W of capacity with ATX 3.1, PCIe 5.1, and fully modular cabling.

Best For: Gaming PCs that benefit from silent low-load operation, modern GPU support, and an 850W ATX supply.

Pros:

• 0RPM fan mode provides silent operation when temperature and output allow.
• 80 Plus Platinum efficiency and 100% Japanese capacitors.
• Includes a PCIe 5.1 12V-2×6 cable rated for up to 600W.
• Fully modular individual cables include cable combs.

Cons:

• Fanless operation is conditional, not continuous at every load.
• The listed warranty description is only one year.

For a quiet desktop, the AMP GH offers the most directly relevant feature in this group: a 0RPM mode. Its 850W output and modern GPU cable also make it suitable for capable gaming systems, provided your expectations account for fan operation under higher thermal or power demands.

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Long-Warranty Quiet Pick – CORSAIR RM850x 850W

CORSAIR RM850x ATX 3.1 PCIe 5.1 Ready Fully Modular 850W Power Supply – Low-Noise, Cybenetics Gold Efficiency, Native 12V-2x6 Connector – Black

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The CORSAIR RM850x is an 850W ATX supply focused on efficient, low-noise operation, although it is not marketed as a fanless computer power supply. Its fully modular layout and native 12V-2×6 connector make installation and current-generation GPU compatibility straightforward.

Best For: Mainstream and high-performance PCs needing efficient 850W power, flexible cabling, and a long warranty.

Pros:

• Cybenetics Gold efficiency rated up to 91%.
• ATX 3.1 compliant with PCIe 5.1 support.
• Native 12V-2×6 connector avoids a GPU adapter.
• Fully modular embossed cables with low-profile combs.

Cons:

• Uses fan-based cooling rather than fanless operation.
• 850W may be more capacity than required for basic systems.

The RM850x is a practical middle ground for buyers who want reduced noise, efficient operation, and clean cable management. Its 10-year manufacturer warranty adds long-term appeal, but shoppers specifically requiring sustained zero-fan operation should look for a model that explicitly provides it.

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How We Picked These Fanless Computer Power Supplies

We selected models across several use cases, including fully fanless ATX supplies, semi-passive ATX units, SFX designs, and DC power modules for Mini-ITX systems. We prioritized current standards such as ATX 3.1 and PCIe 5.1 where available, native 12V-2×6 or high-power GPU support, reputable efficiency certifications, modular cabling, and compatibility with compact cases.

Because “fanless” can describe different designs, check each product’s operating mode carefully. Some supplies are completely passive, while others use a zero-RPM mode that engages the fan only under higher temperatures or loads.

Quick Comparison

Best For	Recommended Type	What to Prioritize
Silent desktop or workstation	Fully fanless ATX	Continuous wattage, airflow, and efficiency
Modern gaming PC	ATX 3.1 semi-passive	Native PCIe 5.1 and 12V-2×6 support
Small-form-factor build	SFX or DC-DC module	Dimensions, output limits, and connectors
Low-power Mini-ITX PC	Pico PSU or DC supply	Input adapter, peak capacity, and protection

Key Buying Factors for Fanless Computer Power Supplies

Wattage and Power Headroom

Estimate the system’s sustained and peak consumption, then leave practical headroom for transient GPU loads, storage, USB devices, and future upgrades. A high wattage rating does not make a unit suitable if the case cannot provide adequate airflow.

Form Factor and Installation

ATX, SFX, and DC power modules are not interchangeable. Confirm the case mounting pattern, cable reach, clearance around modular connectors, and whether an external AC adapter is included or required.

GPU Compatibility

For current graphics cards, prefer ATX 3.1 supplies with native PCIe 5.1 cabling and a 12V-2×6 connector. Avoid relying on overloaded adapters or multiple split cables when the manufacturer specifies a dedicated connection.

Efficiency, Cooling, and Noise

Higher efficiency reduces wasted heat, but passive cooling still depends on case airflow and ambient temperature. A semi-passive model may be the better choice for a high-load system because it can provide active cooling when needed while remaining silent at idle.

Protection and Warranty

Look for overvoltage, undervoltage, overcurrent, short-circuit, and over-temperature protection. A strong warranty and established manufacturer support are especially valuable for expensive components and continuously running systems.

Who Should Buy Which Fanless Computer Power Supplies?

Choose a fully fanless ATX model for a carefully ventilated silent desktop, media PC, or low-noise workstation where the total load is predictable. Choose an ATX 3.1 semi-passive unit for a gaming or creator PC that needs modern GPU support and higher peak capacity. SFX supplies suit compact cases, provided their dimensions and cable layout match the build. Pico PSU and other DC solutions are best for low-power Mini-ITX systems, embedded PCs, and highly compact builds rather than demanding gaming hardware.

Before buying, verify the exact model’s fan behavior, connector set, dimensions, input requirements, and rated output at your expected operating temperature.