13 Best Mini ITX PC Power Supplies, Compared
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Finding the best Mini ITX PC power supplies requires balancing physical dimensions with reliable power delivery. We compared 13 products based strictly on the specifications published on their listings. The FSP 400W Gold Flex ATX Mini ITX Power Supply earns the top spot because it delivers 80 Plus Gold efficiency within compact 1.6 by 3.25 by 5.9 inch dimensions.
This guide helps you choose the right form factor, wattage, and cable configuration for your compact case.
Quick picks
The best fit for you
- You need efficient power for compact NAS server builds FSP 400W Gold Flex ATX Mini ITX Power Supply It delivers 400W with 80 Plus Gold efficiency across standard Flex ATX dimensions.
- You want high wattage for Mini ITX gaming builds be quiet! SFX L 600W Gold Modular Power Supply It features 600W output, 80 Plus Gold efficiency, and four dedicated PCIe connectors for graphics cards.
- You prioritize modular cabling with long warranty coverage Rosewill 500W Fully Modular Mini ITX PSU It delivers 500W through fully modular cables and includes five-year warranty coverage.
- You need completely silent operation in ultra-compact cases FOSA 350W Fanless Mini ITX DC Power Supply Its fanless DC architecture supplies 350W while measuring just 0.79 inches in height.
Our 13 picks
FSP 400W Gold Flex ATX Mini ITX Power Supply
Best for: compact Mini ITX and NAS server builds
- Form Factor
- Mini ITX (what this guide is about)
- Wattage
- 400W
- Efficiency Rating
- 80 Plus Gold
- PCIe Connector Type
- 6+2 pin
- Fan Size
- 4 cm
- Dimensions
- 5.9 × 1.6 × 3.25 inches
View on Amazon: FSP 400W Gold Flex ATX Mini ITX Power Supply
The FSP 400W Flex ATX 80 Plus Gold PSU delivers 400 watts of continuous power inside a compact 5.9 by 1.6 by 3.25-inch chassis. It features an 80 Plus Gold efficiency rating exceeding 90 percent and includes a single 6+2 pin PCIe connector for a dedicated graphics card. A 4 cm internal fan provides airflow. This supply suits you if you build a compact Mini ITX system, home server, or NAS enclosure.
Pros
- 80 Plus Gold certified with over 90% efficiency
- Dedicated 6+2 pin PCIe connector for graphics hardware
- Compact dimensions measuring 5.9 by 1.6 by 3.25 inches
- Rated MTBF of 100K hours at 25°C
Cons
- Small 4 cm fan size
- Single PCIe connector limits dual-cable graphics cards
- Maximum output capped at 400 watts
Good fit if
- You need a compact Flex ATX power supply for a Mini ITX, NAS, or server build.
- You use a graphics card that requires only one 6+2 pin PCIe connector.
- You want 80 Plus Gold efficiency to keep thermal output low.
Skip if
- You need more than 400 watts of total system power.
- You require multiple PCIe power connectors for demanding hardware.
Verdict: FSP 400W Flex ATX 80 Plus Gold PSU provides efficient power delivery in a space-saving footprint for compact builds. It is a dependable choice when you need standard Flex ATX dimensions and basic PCIe graphics card support.
Apevia SFX 400W Power Supply
Best for: Entry-level Mini ITX builds with modest power
- Form Factor
- Mini ITX (what this guide is about)
- Wattage
- 400W
- PCIe Connector Type
- 6/8pin
- Fan Size
- 80mm
- Dimensions
- 5 × 4 × 2.5 inches
- Weight
- 2.03 pounds
The Apevia 400W SFX Mini ITX Power Supply gives you 400 watts of power in a compact 4.92 by 3.94 by 2.5 inch frame. It features an 80mm thermal-sensing fan, sleeved cabling, and a single 6/8-pin PCIe connector paired with a 28A +12V rail. This unit suits you if you assemble a compact Mini ITX chassis running a modest dedicated graphics card.
Pros
- Includes an 80mm thermal-sensing cooling fan
- Delivers up to 28A on the +12V rail
- Comes with fully sleeved cables
- Features a flexible 6/8-pin PCIe connector
Cons
- Provides only two SATA power connectors
- Limited to a single 4-pin 12V CPU power connector
Good fit if
- You need a compact power supply measuring 125mm x 100mm x 63.5mm.
- You run a basic setup requiring only one 6/8-pin PCIe connection.
- You want pre-sleeved wiring in your small-form-factor case.
Skip if
- You have a motherboard that requires an 8-pin CPU power lead.
- You plan to power more than two SATA storage drives.
- You use a high-wattage graphics card needing multiple PCIe cables.
Verdict: Apevia 400W SFX Mini ITX Power Supply provides 400W of cooling-managed power for compact cases. It fits lightweight builds well as long as you do not need more than one 4-pin CPU plug and two SATA drives.
RGEEK Mini ITX DC to DC ATX Power Supply
Best for: compact 12V DC Mini ITX builds
- Form Factor
- Mini ITX (what this guide is about)
- Wattage
- 300W
- Weight
- 6.38 ounces
The RGEEK 300W DC-to-DC Pico Mini ITX Power Supply delivers up to 300W of direct current power in an ultra-compact footprint weighing just 6.38 ounces. It plugs directly into a 24-pin motherboard connector and accepts an 11.2V to 12.6V DC input via a 5.5mm outer, 2.5mm inner diameter barrel jack. This unit suits you if you build a small Mini ITX system using external DC power.
Pros
- Weighs 6.38 ounces for compact installations
- Supports up to 300W power delivery
- Provides built-in short-circuit protection and output shutdown
- Includes defensive functions across +3.3V, +5V, +12V, and +5VSB rails
Cons
- Requires an external 11.2V to 12.6V DC power source
- Limited to a 5.5mm outer and 2.5mm inner diameter input plug
- Caps total power delivery at 300W
Good fit if
- You need a lightweight power module weighing under 7 ounces.
- You plan to run your Mini ITX PC from a 12V direct-current power input.
- You run components that stay within the 300W ceiling.
Skip if
- You need an internal power supply that connects directly to AC wall outlets.
- You run demanding hardware requiring more than 300W of capacity.
Verdict: RGEEK 300W DC-to-DC Pico Mini ITX Power Supply delivers direct-current power for compact builds with strict space and weight constraints. It provides essential rail protections and 300W output for low-draw setups powered by external 12V adapters.
FOSA 350W Fanless Mini ITX DC Power Supply
Best for: silent ultra-compact Mini ITX builds
- Form Factor
- Mini ITX (what this guide is about)
- Wattage
- 350W
- Dimensions
- 6.06 × 1.38 × 0.79 inches
- Weight
- 7.88 ounces
The FOSA 350W Fanless Mini ITX DC Power Supply provides a compact DC-to-DC power solution for ultra-small systems. Delivering 350W with 85%+ efficiency, it operates without a fan for zero acoustic noise. Its slim profile measures 6.06 by 1.38 by 0.79 inches, making it suitable if you are building an ultra-compact home theater PC or a quiet office desktop where standard internal supplies cannot fit.
Pros
- Fanless design enables completely silent operation
- Delivers 350W output with 85%+ efficiency
- Ultra-compact dimensions of 6.06 x 1.38 x 0.79 inches
- Integrated overvoltage and short-circuit protection
Cons
- Total power output is limited to 350W
- Maximum operating temperature is limited to 40°C
Good fit if
- You need a fanless, zero-noise power solution for a Mini ITX build
- You are assembling an ultra-compact chassis with very tight clearance
- Your hardware components require 350W of power or less
Skip if
- You require more than 350W for higher-power components
- Your system operates in ambient environments exceeding 40°C
Verdict: FOSA 350W Fanless Mini ITX DC Power Supply delivers silent, fan-free operation and solid 85%+ efficiency for small-form-factor systems. It is an effective option when your compact chassis cannot fit standard power supplies and requires 350W or less.
be quiet! SFX L 600W Gold Modular Power Supply
Best for: high-power Mini ITX gaming builds
- Form Factor
- Mini ITX (what this guide is about)
- Wattage
- 600W
- Efficiency Rating
- 80 PLUS Gold
- Modularity
- Modular
- Fan Size
- 120mm
- Warranty
- 3-Year
View on Amazon: be quiet! SFX L 600W Gold Modular Power Supply
The be quiet! SFX-L 600W is a modular power supply built for compact Mini ITX cases that support SFX-L units. It provides 600 watts of output with 80 Plus Gold efficiency and features modular cabling to simplify interior routing. A temperature-controlled 120mm fan manages heat during operation. You also get four PCIe connectors for multi-GPU setups. It suits builders who need clean cable management in small-form-factor systems.
Pros
- 80 Plus Gold certification reaching up to 92% efficiency
- Modular cable system for uncluttered interior routing
- Temperature-controlled 120mm cooling fan
- Equipped with four PCIe power connectors
Cons
- 5.12-inch SFX-L length is longer than standard SFX units
- Warranty is limited to 3 years
Good fit if
- You need 600 watts of modular power in a Mini ITX enclosure that accommodates SFX-L dimensions.
- You run a hardware configuration requiring up to four PCIe power connectors.
- You plan to mount an SFX unit inside a standard ATX case using the included bracket.
Skip if
- You have an ultra-compact chassis restricted strictly to standard 100mm SFX or Flex ATX form factors.
- You require a power supply backed by a manufacturer warranty longer than three years.
Verdict: be quiet! SFX-L 600W Modular Power Supply delivers efficient 80 Plus Gold power, modular cables, and four PCIe connectors for compact performance builds. Its 5.12-inch length requires a chassis with adequate SFX-L clearance, but the included 120mm fan and ATX bracket ensure versatile installation.
Apevia SFX 500W Small Form Factor Power Supply
Best for: single-GPU Mini ITX and Micro ATX builds
- Form Factor
- Mini ITX (what this guide is about)
- Wattage
- 500W
- PCIe Connector Type
- 6+2 pin
- Dimensions
- 4.92 × 3.94 × 2.5 inches
View on Amazon: Apevia SFX 500W Small Form Factor Power Supply
The Apevia 500W SFX Power Supply provides 500 watts of output in a compact chassis measuring 4.9 inches long, 3.94 inches wide, and 2.5 inches high. It features one 6+2-pin PCIe connector, one 4+4-pin CPU connection, three SATA ports, and two 4-pin Molex plugs. This unit suits you if you build a small form factor Mini ITX or Micro ATX system requiring moderate wattage.
Pros
- 500W output in a compact 4.9 by 3.94 by 2.5-inch footprint
- Split 6+2-pin PCIe connector accommodates 6-pin or 8-pin graphics cards
- Split 4+4-pin CPU connector supports 4-pin and 8-pin motherboards
- Includes three SATA and two 4-pin Molex peripheral connections
Cons
- Single PCIe connector limits dual-cable graphics configurations
- No 80 Plus efficiency certification listed in specifications
Good fit if
- You need a 500W power supply for a Mini ITX, Micro ATX, or SFX build.
- You use a graphics card requiring only a single 6-pin or 8-pin PCIe power cable.
- You require legacy 4-pin Molex connectors alongside standard SATA storage.
Skip if
- You need multiple PCIe power cables for high-draw graphics cards.
- You require an explicit 80 Plus efficiency rating listed in the specifications.
Verdict: Apevia 500W SFX Power Supply delivers 500 watts of power with versatile split connectors for compact cases. It provides essential connections for basic builds that do not need multiple graphics card power cables.
T.F.SKYWINDINTL 600W Fully Modular Flex ATX PSU
Best for: high-wattage modular Flex ATX PC builds
- Form Factor
- Mini ITX (what this guide is about)
- Wattage
- 600W
- Modularity
- Fully Modular
- Dimensions
- 6.5 × 3.27 × 1.57 inches
- Weight
- 2.47 pounds
View on Amazon: T.F.SKYWINDINTL 600W Fully Modular Flex ATX PSU
This unit from T.F.SKYWINDINTL is a 600-watt Flex ATX power supply designed for compact Mini ITX cases and 1U servers. Its fully modular design lets you attach only the cables you need to improve internal airflow. Built with Japanese capacitors and a DC-to-DC topology, it delivers stable power under full 100 to 240-volt AC input. It suits you if you need high wattage and clean cable management in a small enclosure.
Pros
- Fully modular cabling to reduce clutter and improve airflow
- 600W output in a standard Flex ATX form factor
- Built with 100% Japanese capacitors and DC-to-DC circuitry
- Full-range 100-240V AC input with Active PFC
- Includes OVP, UVP, OCP, OPP, SCP, and OTP protections
Cons
- Only compatible with the specific modular cables packaged in the box
- No official 80 Plus efficiency certification listed in specifications
- Length of 165 mm is longer than some standard Flex ATX units
Good fit if
- You need a 600W fully modular power supply for a Flex ATX or 1U build.
- You want Japanese capacitors and DC-to-DC power regulation.
- You require full-range 100-240V voltage compatibility.
Skip if
- You require an independently verified 80 Plus efficiency badge.
- You have a case that cannot fit a 165 mm long power supply.
- You plan to use custom third-party modular cables.
Verdict: T.F.SKYWINDINTL 600W Fully Modular Flex ATX PSU provides high wattage and modular cabling for tight Mini ITX and 1U server chassis. It combines Japanese capacitors with full electrical protections for dependable small-form-factor builds.
ESGAMING 500W Flex ATX Modular PSU
Best for: compact 1U Flex ATX 500W builds
- Form Factor
- Mini ITX (what this guide is about)
- Wattage
- 500W
- Efficiency Rating
- 80 PLUS Bronze
- Modularity
- Fully Modular
- PCIe Connector Type
- 6+2 PCIE
- Dimensions
- 6.3 × 2.87 × 1.38 inches
The ESGAMING 500W is a 1U Flex ATX power supply designed for compact Mini ITX cases, NAS systems, and HTPC setups. It delivers 500 watts of output with an 80 Plus Bronze efficiency rating reaching up to 85 percent. You get a fully modular cable layout with two 6+2 PCIe connectors, which helps you reduce cable clutter and improve airflow inside narrow chassis.
Pros
- Fully modular cable system simplifies routing in tight enclosures
- 80 Plus Bronze rating delivers up to 85% energy efficiency
- Two 6+2 PCIe connectors for dedicated graphics cards
- Built-in OVP, OCP, OPP, and SCP electrical safeguards
Cons
- Includes only two SATA connectors for storage drives
- 80 Plus Bronze efficiency falls below Gold-rated models
Good fit if
- You need a fully modular 500W power supply for a 1U or Flex ATX enclosure.
- You build a system requiring up to two 6+2 pin PCIe power leads.
Skip if
- You require more than two SATA storage drives.
- You want efficiency higher than 80 Plus Bronze.
Verdict: ESGAMING 500W Fully Modular Flex ATX PSU delivers reliable 500-watt output in a compact 1U form factor with modular cabling. It provides dedicated PCIe connectivity and standard electrical protections for small-form-factor builds.
T.F.SKYWINDINTL 600W Modular Mini ITX PSU
Best for: Dual-CPU small form factor Mini ITX systems
- Form Factor
- Mini ITX (what this guide is about)
- Wattage
- 600W
- Modularity
- Fully Modular
- Fan Size
- 40mm
- Dimensions
- 6.5 × 3.23 × 1.61 inches
- Weight
- 2.58 pounds
This 600W Flex ATX power supply from T.F.SKYWINDINTL delivers compact power for Mini ITX, Micro ATX, and HTPC cases. It features a fully modular design to help you manage clutter and improve airflow in tight enclosures. With its dual 8-pin CPU connectors, active PFC, and a 40mm temperature-controlled fan, this unit suits you if you need high power density for dual-processor configurations or compact multi-core systems.
Pros
- Fully modular cable system reduces internal clutter in small cases
- Dual 8-pin CPU power connectors support dual-processor configurations
- Compact dimensions of 165 by 81.5 by 41 mm fit 1U and Mini ITX enclosures
- Rated for 24/7 continuous operation at 40°C
- Active PFC with overvoltage, overcurrent, and short-circuit protections
Cons
- Includes only one PCIe power cable
- Relies on a small 40mm cooling fan
Good fit if
- You need dual 8-pin CPU connectors in a compact Mini ITX or Flex ATX build.
- You want fully modular cabling to maximize airflow in a tight enclosure.
- You require continuous 24/7 operation at ambient temperatures up to 40°C.
Skip if
- You need more than one dedicated PCIe cable for your graphics card.
- You prefer power supplies with larger fans than 40mm.
Verdict: T.F.SKYWINDINTL 600W Modular Flex ATX PSU provides high power density and dual CPU connectivity in a compact, fully modular chassis. It is a capable option for small form factor setups that require dedicated dual-processor support.
ESGAMING 400W Modular Flex ATX PSU
Best for: compact NAS or Mini ITX 1U builds
- Form Factor
- Mini ITX (what this guide is about)
- Wattage
- 400W
- Efficiency Rating
- 80 Plus Bronze
- Modularity
- Fully Modular
- PCIe Connector Type
- 6+2 PCIE
- Dimensions
- 6.3 × 2.87 × 1.38 inches
This ESGAMING unit is a compact 400W Flex ATX power supply designed for Mini ITX systems, 1U chassis, and small NAS builds. You get an 80 Plus Bronze efficiency rating delivering up to 85% efficiency, alongside a fully modular cable setup that helps keep your compact case clear of clutter. It suits you if you need dedicated graphics support via two 6+2 pin PCIe connectors within a tight 1.38-inch profile.
Pros
- Fully modular cable design
- Two 6+2 pin PCIe connectors
- 80 Plus Bronze certified for up to 85% efficiency
- Compact 1U Flex ATX dimensions of 6.3 x 2.87 x 1.38 inches
Cons
- 400W maximum capacity limits component power draw
- Only includes two SATA power connectors
- Efficiency limited to 80 Plus Bronze level
Good fit if
- You need a fully modular Flex ATX supply to maximize airflow in a small enclosure.
- You run a low-power Mini ITX or 1U build with a PCIe graphics card.
- You want built-in circuit safeguards including OVP, OCP, OPP, and SCP.
Skip if
- You require more than 400W for high-draw CPU and GPU combinations.
- You need power connections for more than two SATA storage drives.
- You want an 80 Plus Gold or higher efficiency rating.
Verdict: ESGAMING 400W Fully Modular Flex ATX Power Supply delivers modular cabling and dual PCIe connections in a compact 1U form factor for sub-400W systems. It provides Bronze-certified efficiency and core circuit protections for small desktop or NAS cases.
T.F.SKYWINDINTL 600W Fully Modular Flex ATX PSU
Best for: compact Mini-ITX and 1U builds requiring modular cabling
- Form Factor
- Mini ITX (what this guide is about)
- Wattage
- 600W
- Modularity
- Fully Modular
- PCIe Connector Type
- 6+2pin
- Power Factor Correction
- Active PFC
- Dimensions
- 6.5 × 3.27 × 1.57 inches
View on Amazon: T.F.SKYWINDINTL 600W Fully Modular Flex ATX PSU
This 600W unit provides a fully modular layout inside a compact 1U Flex ATX frame measuring 6.5 by 3.27 by 1.57 inches. It includes Japanese capacitors, DC-DC topology, Active PFC, and comprehensive electrical protections (OVP, UVP, OCP, OPP, SCP, OTP). If you build inside cramped Mini-ITX cases or compact 1U rackmount chassis that demand modular cable management to maintain airflow, this power supply fits your hardware specifications directly.
Pros
- Fully modular cable design simplifies routing in tight spaces
- Compact dimensions of 6.5 by 3.27 by 1.57 inches fit 1U Flex ATX slots
- Built with Japanese capacitors and DC-to-DC architecture
- Comprehensive protection suite includes OVP, UVP, OCP, OPP, SCP, and OTP
Cons
- No official 80 Plus efficiency certification listed in specifications
- Includes only a single PCIe cable run with 6+2-pin connectivity
Good fit if
- You need a 600W fully modular power supply for a small form factor or 1U build.
- You want Japanese capacitors and Active PFC in a compact Flex ATX footprint.
Skip if
- You require an official 80 Plus efficiency tier listed on the spec sheet.
- You need multiple separate PCIe power cables for high-draw graphics cards.
Verdict: T.F.SKYWINDINTL 600W Fully Modular Flex ATX PSU delivers high wattage and detachable cables for tight 1U and Mini ITX enclosures. Its Japanese capacitors and compact dimensions make it a practical fit when chassis space is strictly limited.
RGEEK 600W Modular Flex ATX PSU
Best for: Mini ITX builds needing PCIe 5.0 support
- Form Factor
- Mini ITX (what this guide is about)
- Wattage
- 600W
- Modularity
- Fully Modular
- PCIe Connector Type
- 12VHPWR, 12V-2x6, 6+2Pin
- Dimensions
- 6.5 × 3.35 × 1.59 inches
- Weight
- 2.94 pounds
This RGEEK 600W unit provides a fully modular Flex ATX design for compact Mini ITX builds, NAS units, and 1U enclosures. You get an efficiency rating over 92 percent, full Japanese capacitors, and a dedicated 12VHPWR connector for PCIe 5.0 GPUs alongside standard PCIe 6+2-pin and CPU power lines. Its small footprint and detachable cables suit you when space and cable management are strictly limited.
Pros
- Includes 16-pin 12VHPWR cable for PCIe 5.0 hardware
- Over 92% efficiency rating with full Japanese capacitors
- Fully modular design with detachable embossed PVC cables
- Delivers 50A on the +12V rail
Cons
- Includes only two SATA power connectors
- Uses a small 4020 cooling fan
- Requires plugging in a separate 3-pin sense wire on the main cable
Good fit if
- You need a compact Flex ATX unit with PCIe 5.0 12VHPWR support.
- You want fully modular cables to maximize airflow in an SFF chassis.
- You run a system requiring up to 50A on the +12V rail.
Skip if
- You need more than two SATA storage drives without adapters.
- You require traditional 4-pin peripheral Molex connectors.
Verdict: RGEEK 600W Modular Flex ATX PSU provides high single-rail output and modern 12VHPWR cabling in an ultra-compact modular footprint. It delivers efficient power distribution for space-constrained Mini ITX and 1U server chassis.
Rosewill 500W Fully Modular Mini ITX PSU
Best for: Mini ITX systems needing long warranty coverage
- Form Factor
- Mini ITX (what this guide is about)
- Wattage
- 500W
- Modularity
- Fully Modular
- PCIe Connector Type
- 6+2 pin
- Fan Size
- 40mm
- Warranty
- 5-year
The Rosewill 500W Fully Modular Flex ATX PSU provides 500 watts of power in a compact 1U form factor measuring 1.57 inches tall. It features a fully modular cable design, allowing you to attach only needed leads. Built-in industrial protections include OVP, OPP, OCP, and SCP, paired with a five-year warranty. It fits your space-constrained Mini ITX case or small form factor build requiring dedicated PCIe power.
Pros
- Five-year manufacturer warranty
- Fully modular cabling design
- Two 6+2 pin PCIe connectors included
- Full range Active PFC 90-264V support
Cons
- Small 40mm cooling fan
- Limited to two SATA power connectors
Good fit if
- You need a 500W Flex ATX unit backed by a five-year warranty.
- You want fully modular cables to reduce clutter in a compact enclosure.
- You need dual 6+2 pin PCIe connectors for a dedicated graphics card.
Skip if
- You need to power more than two SATA storage drives.
- You require a power supply with a fan larger than 40mm.
Verdict: Rosewill 500W Fully Modular Flex ATX PSU delivers dependable 500W power and modular cable management for dense enclosures. Its five-year warranty offers extended protection rarely seen in small 1U units.
Specifications side by side
| Spec | FSP 400W Gold Flex ATX Mini ITX Power Supply | Apevia SFX 400W Power Supply | RGEEK Mini ITX DC to DC ATX Power Supply | FOSA 350W Fanless Mini ITX DC Power Supply | be quiet! SFX L 600W Gold Modular Power Supply | Apevia SFX 500W Small Form Factor Power Supply | T.F.SKYWINDINTL 600W Fully Modular Flex ATX PSU | ESGAMING 500W Flex ATX Modular PSU | T.F.SKYWINDINTL 600W Modular Mini ITX PSU | ESGAMING 400W Modular Flex ATX PSU | T.F.SKYWINDINTL 600W Fully Modular Flex ATX PSU | RGEEK 600W Modular Flex ATX PSU | Rosewill 500W Fully Modular Mini ITX PSU |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Wattage | 400W | 400W | 300W | 350W | 600W | 500W | 600W | 500W | 600W | 400W | 600W | 600W | 500W |
| Efficiency Rating | 80 Plus Gold | not specified | not specified | not specified | 80 PLUS Gold | not specified | not specified | 80 PLUS Bronze | not specified | 80 Plus Bronze | not specified | not specified | not specified |
| Modularity | not specified | not specified | not specified | not specified | Modular | not specified | Fully Modular | Fully Modular | Fully Modular | Fully Modular | Fully Modular | Fully Modular | Fully Modular |
| PCIe Connector Type | 6+2 pin | 6/8pin | not specified | not specified | not specified | 6+2 pin | not specified | 6+2 PCIE | not specified | 6+2 PCIE | 6+2pin | 12VHPWR, 12V-2x6, 6+2Pin | 6+2 pin |
| Fan Size | 4 cm | 80mm | not specified | not specified | 120mm | not specified | not specified | not specified | 40mm | not specified | not specified | not specified | 40mm |
| Warranty | not specified | not specified | not specified | not specified | 3-Year | not specified | not specified | not specified | not specified | not specified | not specified | not specified | 5-year |
| Form Factor | Mini ITX | Mini ITX | Mini ITX | Mini ITX | Mini ITX | Mini ITX | Mini ITX | Mini ITX | Mini ITX | Mini ITX | Mini ITX | Mini ITX | Mini ITX |
| Recommended Use | not specified | not specified | not specified | not specified | Gaming | not specified | not specified | not specified | not specified | not specified | not specified | not specified | not specified |
| Power Factor Correction | not specified | not specified | not specified | not specified | not specified | not specified | not specified | not specified | not specified | not specified | Active PFC | not specified | Active PFC |
| Size | 400W_Gold | not specified | not specified | not specified | 600W | not specified | 165*83*40mm | 500W | 165*81.5*41mm | not specified | not specified | not specified | Mini ITX/Flex ATX |
| Device Compatibility | not specified | not specified | not specified | not specified | not specified | not specified | not specified | not specified | not specified | not specified | not specified | not specified | NAS |
| Dimensions | 5.9 × 1.6 × 3.25 inches | 5 × 4 × 2.5 inches | not specified | 6.06 × 1.38 × 0.79 inches | 5.12 × 4.92 × 2.52 inches | 4.92 × 3.94 × 2.5 inches | 6.5 × 3.27 × 1.57 inches | 6.3 × 2.87 × 1.38 inches | 6.5 × 3.23 × 1.61 inches | 6.3 × 2.87 × 1.38 inches | 6.5 × 3.27 × 1.57 inches | 6.5 × 3.35 × 1.59 inches | 6.5 × 3.15 × 1.57 inches |
| Weight | 2 pounds | 2.03 pounds | 6.38 ounces | 7.88 ounces | 2.56 pounds | not specified | 2.47 pounds | not specified | 2.58 pounds | not specified | 2.2 pounds | 2.94 pounds | 1.43 pounds |
| Model | FSP400-60FGGBA | SFX-AP400W | LR1106-250W12VDC | not specified | BN639 | SFX-AP500W | TF600 | 1U500W | FLEX 600-W | 1U400W | Mini ITX 600W-Black | not specified | VIT500 |
| Color | not specified | not specified | not specified | default | Black | not specified | black | not specified | white | not specified | black | not specified | Black |
Is a Mini ITX Power Supply Worth It?
A Mini ITX power supply changes how much hardware you can fit inside tight enclosures like compact desktops and 1U racks. Choosing this form factor gives you chassis compatibility with small volumes, lowering unit weights down to under eight ounces for DC-to-DC boards or between 1.4 and 3 pounds for enclosed units. However, compact form factors limit available capacity to between 300W and 600W across these models, and require checking whether you need modular cabling, external 12V DC input, or dedicated PCIe power cables.
Worth it if
- You assemble a compact desktop, NAS, or 1U server chassis that cannot house standard-size components.
- You build a low-draw system using an external 12V DC adapter or fanless silent hardware.
- You need a modular unit under 6.5 inches long that still provides dedicated PCIe graphics connectivity.
Skip it if
- You require more than 600 watts of total power output for high-draw hardware.
- You assemble a full-size case with ample mounting clearance for standard ATX power components.
Before you select your power supply form factor, review clearance specifications across the best Mini-ITX PC cases to confirm your hardware fits.
How We Picked These Units
We identified eligible models by finding listings that specify the Mini ITX form factor in their title or published specifications. Each listing provides the exact technical details used here; products are not physically handled. To ensure variety across the guide, we display only one size or variant per product family.
Products in stock appear first. You can evaluate the 13 featured units by critical specifications such as exterior dimensions, total wattage, and modular cabling support. Live availability updates at least daily to help you plan your build for 2026.
How to Choose a Mini ITX Power Supply
-
Cable Management and Modularity
Mini ITX enclosures leave little space for excess wiring. Choosing between fixed and fully modular cables impacts how easily air moves through your case. Fixed cables force you to bundle unused wires inside tight corners, which restricts ventilation. A fully modular unit lets you attach only the specific cables your motherboard and storage require. If you build inside a compact 1U or Mini ITX chassis, look for modular cabling. The T.F.SKYWINDINTL 600W Fully Modular Flex ATX PSU provides detachable cables to keep your enclosure free from unnecessary wire clutter.
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Efficiency Ratings and Heat
Power efficiency ratings show how much electricity is lost as thermal waste. In small-form-factor systems, trapped heat can quickly raise internal case temperatures. Look for published certifications such as 80 Plus Bronze or 80 Plus Gold. A higher efficiency rating means less energy turns into heat, keeping your components cooler during operation. For compact Mini ITX builds and NAS setups that run continuously, higher efficiency is ideal. The FSP 400W Gold Flex ATX Mini ITX Power Supply carries an 80 Plus Gold rating, delivering efficient power while reducing overall thermal output.
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Dedicated Graphics Connector Support
Graphics card requirements vary widely based on your target hardware. Some entry-level units offer only basic CPU and SATA connectors, while others include dedicated PCIe power plugs. If you intend to install a modern graphics card, verify the exact connector standard before buying. Check whether the power supply includes traditional 6-pin or 8-pin PCIe cables, or updated connectors. For setups requiring newer GPU connections, the RGEEK 600W Modular Flex ATX PSU includes 12VHPWR cabling to supply graphics cards that rely on the PCIe 5.0 standard without needing extra adapters.
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External Versus Internal Power
Not all Mini ITX power supplies connect directly to standard wall outlets. Traditional internal units take standard alternating current from an AC wall plug, but ultra-compact systems often use DC-to-DC converters. These direct-current boards require an external 12V power brick to deliver energy to the system. This setup removes the heat and bulk of an AC transformer from inside the chassis. The RGEEK Mini ITX DC to DC ATX Power Supply uses direct-current input to power low-draw builds, making it suitable when internal chassis space cannot accommodate an internal AC supply.
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Active Cooling Versus Fanless
Cooling hardware directly affects the noise levels and thermal balance of your build. Most Mini ITX units rely on small internal fans, such as 40mm or 120mm fans, to pull heat away from internal components. If your build prioritizes zero noise, look for fanless models designed with passive heat dissipation. Fanless units operate in complete silence but require adequate passive ventilation in the surrounding case. The FOSA 350W Fanless Mini ITX DC Power Supply operates without an active fan, making it a functional match for silent ultra-compact systems.
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Warranty and Component Protection
Small power supplies operate under demanding thermal conditions, making build quality and warranty terms critical specifications to review. Look for units that include Active Power Factor Correction, known as Active PFC, and standard rail protections to safeguard connected parts against power fluctuations. Check manufacturer warranty periods, as coverage can range from basic terms to multi-year policies. The Rosewill 500W Fully Modular Mini ITX PSU features Active PFC and provides five-year warranty coverage, offering extended protection that is uncommon in high-density Flex ATX power hardware.
Frequently asked questions
What is the difference between SFX and Flex ATX power supplies?
SFX and Flex ATX power supplies use different physical dimensions to fit specific compact case designs. Flex ATX units, like the 2-pound FSP 400W, feature narrow, elongated profiles measuring around 1.6 inches high. SFX supplies, such as the Apevia SFX-AP400W, use wider, blockier enclosures measuring 4 inches wide and 2.5 inches tall. You must check your chassis bracket layout before choosing a form factor.
Can a Mini ITX power supply run a modern dedicated graphics card?
Yes, many Mini ITX power supplies include dedicated PCIe cabling for modern graphics cards. The RGEEK 600W Flex ATX unit supplies a 12VHPWR connector for current PCIe 5.0 hardware. Other options, like the ESGAMING 400W and 500W models, deliver dedicated dual PCIe connectors. However, entry units like the Apevia 400W SFX model suit low-draw setups without multi-cable graphics card requirements.
How does a DC-to-DC power supply work in a Mini ITX build?
A DC-to-DC power supply converts direct current from an external power brick directly into internal voltages for motherboard components. Units like the 6.38-ounce RGEEK 300W connect internally to standard motherboard headers without needing internal AC transformation hardware. This setup reduces internal clutter and eliminates heavy enclosures, making it suitable for ultra-compact systems with low power demands and strict weight constraints.
Are fanless Mini ITX power supplies completely silent?
Yes, fanless Mini ITX power supplies operate with zero acoustic noise because they lack mechanical cooling fans. The FOSA 350W DC unit relies entirely on passive heat dissipation and operates at over 85% efficiency. It measures 0.79 inches tall and weighs 7.88 ounces, fitting into spaces where moving parts are impractical. You must ensure your computer case provides adequate passive ventilation to dissipate heat.
Can you install a Mini ITX power supply into a standard ATX case?
You can install a Mini ITX power supply into an ATX case if you use an appropriate mounting bracket. Units such as the be quiet! SFX L 600W include an ATX adapter bracket specifically designed to bridge the size difference. Without an adapter bracket, the smaller screw hole pattern of SFX or Flex ATX enclosures will not align with standard ATX chassis mounting cutouts.
What power supply features should you look for in a dual-CPU Mini ITX system?
You need a unit equipped with dual dedicated EPS or CPU power connections and sufficient continuous wattage. The T.F.SKYWINDINTL 600W white model (FLEX 600-W) specifically delivers dual-processor support in a modular 165 by 81.5 by 41 millimeter frame. Standard compact units often provide only one 4-pin or 8-pin connector, which will prevent a dual-socket workstation or server motherboard from powering on properly.
What does Active PFC do in a Mini ITX power supply?
Active PFC, or Active Power Factor Correction, aligns the electrical current waveform with voltage to increase power delivery efficiency from the wall. Models like the Rosewill VIT500 and T.F.SKYWINDINTL 600W Black feature Active PFC circuitry to minimize wasted reactive power. This standard feature helps regulate input power cleanly, reducing load stress on small-scale electrical systems while your Mini ITX hardware runs.