Best ATX 3.1 PC Power Supplies: 15 Spec-Based Picks
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Choosing an ATX 31 PC power supply ensures your desktop reliably handles transient power spikes from modern graphics hardware. We evaluated 15 models strictly using the technical specifications published on their manufacturer listings. The MSI MAG 850W Fully Modular ATX Power Supply earns the top position because it pairs 80 Plus Gold efficiency with a native 12V-2x6 connector and a 10-year warranty.
This breakdown helps you decide which model matches your build requirements, balancing wattage capacity, overall dimensions, and modular cable setups for clean installation.
Quick picks
The best fit for you
- You build a standard 850W ATX 3.1 gaming rig MSI MAG 850W Fully Modular ATX Power Supply It delivers 850W output, ATX 3.1 compliance, a 12V-2x6 connector, and a 10-year warranty.
- You need 1000W output for high-demand modern hardware Corsair RM1000x 1000W ATX 3.1 PSU It provides 1000W capacity, ATX 3.1 compliance, and a dedicated 12V-2x6 connector.
- You want a 750W supply for a white build Corsair RM750x Shift White 750W ATX Power Supply It features a white chassis, 750W capacity, and 80 Plus Gold efficiency.
- You need extreme wattage with peak electrical efficiency ASUS ROG Thor Titanium III 1600W ATX 3.1 PSU It delivers 1600W capacity paired with an 80 Plus Titanium efficiency rating.
Our 15 picks
MSI MAG 850W Fully Modular ATX Power Supply
Best for: standard gaming builds requiring ATX 3.1 power
- ATX Version
- ATX 3.1
- Wattage
- 850W
- Efficiency Rating
- 80+ Gold
- Modularity
- Fully Modular
- PCIe Connector Type
- 12V-2x6
- Warranty
- 10 Year
View on Amazon: MSI MAG 850W Fully Modular ATX Power Supply (paid link)
This MSI power supply delivers 850W of continuous output using the ATX 3.1 standard and PCIe 5.1 specification. You get a fully modular cable design alongside a dedicated 12V-2x6 connector for modern graphics cards. Its 80 Plus Gold efficiency keeps power conversion losses low during gaming. This unit suits you if you need a standard ATX power supply backed by a 10-year warranty for your gaming build.
Pros
- ATX 3.1 compliant with native PCIe 5.1 12V-2x6 connector
- 80 Plus Gold certified efficiency
- Fully modular cabling configuration
- 10-year warranty coverage
Cons
- 850W capacity limits headroom for systems needing 1000W or more
- Efficiency capped at 80 Plus Gold rather than Platinum or Titanium
Good fit if
- You need an 850W ATX 3.1 power supply with a native 12V-2x6 connector.
- You want a fully modular unit backed by a 10-year warranty.
Skip if
- You require 1000W or higher capacity for high-draw hardware configurations.
- You seek 80 Plus Platinum or Titanium efficiency levels.
Verdict: MSI MAG 850W ATX 3.1 Gold Power Supply provides modern ATX 3.1 compliance, PCIe 5.1 hardware support, and fully modular cabling for 850W builds. A 10-year warranty secures long-term operation.
Corsair RM850x 850W Fully Modular ATX 3.1 PSU
Best for: Modern 850W ATX 3.1 graphics card builds
- ATX Version
- ATX 3.1
- Wattage
- 850W
- Efficiency Rating
- Cybenetics Gold
- Modularity
- Fully Modular
- PCIe Connector Type
- 12V-2x6
- PCIe Version
- PCIe 5.1
View on Amazon: Corsair RM850x 850W Fully Modular ATX 3.1 PSU (paid link)
The Corsair RM850x is an 850W ATX power supply designed for modern hardware standards. It features ATX 3.1 compliance and native PCIe 5.1 support via an included 12V-2x6 connector. You get a fully modular black design that allows you to connect only the cables your build requires. This unit suits you if you need an 850W capacity foundation for current-generation graphics cards without excess wiring.
Pros
- Compliant with ATX 3.1 standards
- PCIe 5.1 ready with a native 12V-2x6 connector
- Fully modular cabling configuration
- 850W power output capacity
Cons
- 850W output limit may restrict high-draw multi-GPU systems
- Chassis finish only listed in black
Good fit if
- You need a dedicated 12V-2x6 connector for PCIe 5.1 hardware.
- You want a fully modular 850W unit to minimize internal case cable clutter.
Skip if
- You need more than 850W of total capacity for power-heavy configurations.
- You require a white power supply to match your case color scheme.
Verdict: Corsair RM850x 850W ATX 3.1 Power Supply provides ATX 3.1 compliance and a 12V-2x6 connector in a fully modular format. It delivers 850W of output suitable for modern single-GPU configurations.
Corsair RM1000x 1000W ATX 3.1 PSU
Best for: high-power systems needing ATX 3.1 support
- ATX Version
- ATX 3.1
- Wattage
- 1000W
- Efficiency Rating
- Cybenetics Gold
- Modularity
- Fully Modular
- PCIe Connector Type
- 12V-2x6
- PCIe Version
- PCIe 5.1
View on Amazon: Corsair RM1000x 1000W ATX 3.1 PSU (paid link)
This is a 1000W fully modular power supply built in the standard ATX form factor. It meets ATX 3.1 and PCIe 5.1 specifications, providing a dedicated 12V-2x6 connector for modern graphics cards. The fully modular cabling lets you attach only the leads your hardware requires. It suits you if you are assembling a high-draw gaming or workstation build and need native PCIe 5.1 power delivery.
Pros
- ATX 3.1 compliant and supports PCIe 5.1
- Native 12V-2x6 power connector included
- 1000W capacity for high-draw systems
- Fully modular cabling configuration
Cons
- Available only in black finish
- Weighs 6.88 pounds
Good fit if
- You need 1000W of power for high-demand hardware components.
- You want ATX 3.1 compliance with a dedicated 12V-2x6 connector.
- You prefer a fully modular layout to connect only required cables.
Skip if
- You are planning an all-white component build.
- You need a lower-wattage unit for an entry-level system.
Verdict: Corsair 1000W Fully Modular ATX Power Supply provides ATX 3.1 compliance and a 12V-2x6 connector for high-power modern graphics hardware. Its 1000W output and fully modular design deliver clean cable management for demanding systems.
Corsair RM750x Shift White 750W ATX Power Supply
Best for: mid-range ATX 3.1 builds with side-cable clearance
- ATX Version
- ATX 3.1
- Wattage
- 750W
- Efficiency Rating
- 80 Plus Gold
- Modularity
- Fully Modular
- Fan Size
- 140mm
- PCIe Version
- PCIe 5.1
View on Amazon: Corsair RM750x Shift White 750W ATX Power Supply (paid link)
The Corsair RM750x Shift 750W Power Supply delivers 750 watts of power with native ATX 3.1 and PCIe 5.1 compliance. It features an 80 Plus Gold efficiency certification, 100% Japanese 105°C capacitors, and a 140mm fluid dynamic bearing fan with Zero RPM mode. Its side-mounted micro-fit connections make cable routing easier in compatible chassis. This unit suits you if you are building a mid-range system and want organized cable access.
Pros
- Side-mounted modular interface simplifies cable installation
- Certified Intel ATX 3.1 and PCIe 5.1 compliant
- 80 Plus Gold efficiency rating
- 140mm fluid dynamic bearing fan with Zero RPM mode
- 100% Japanese 105°C-rated electrolytic capacitors
Cons
- 750W total output offers less overhead than higher-wattage models
- Side cable positioning requires dedicated side clearance in your case
- Requires Corsair Type 5 Gen 1 micro-fit cables
Good fit if
- You need an ATX 3.1 compliant 750W unit for a mid-tier configuration.
- You have a PC case with clear side access behind the power supply bay.
- You want an 80 Plus Gold power supply with a white enclosure.
Skip if
- You require 850W or more for power-intensive components.
- Your chassis lacks sufficient clearance beside the PSU bay for side-plugging cables.
Verdict: Corsair RM750x Shift 750W Power Supply is a solid ATX 3.1 option offering 80 Plus Gold efficiency and easy side-access cabling. It works well if your build needs 750W and your case fits side connectors.
Corsair RM850x Shift 850W White ATX Power Supply
Best for: White ATX 3.1 desktop builds
- ATX Version
- ATX 3.1
- Wattage
- 850W
- Efficiency Rating
- 80 Plus Gold
- Modularity
- Fully Modular
- PCIe Connector Type
- PCIe 5.1
- Dimensions
- 6.3 × 5.91 × 3.39 inches
View on Amazon: Corsair RM850x Shift 850W White ATX Power Supply (paid link)
This white 850W power supply supports the ATX 3.1 and PCIe 5.1 standards to power modern desktop hardware. It features 80 Plus Gold certified efficiency and a fully modular layout measuring 6.3 inches long. The side-mounted modular connector interface assists internal cable management in compatible enclosures. You will find it ideal for mid-to-high-tier white computer builds needing dependable 850-watt power delivery.
Pros
- ATX 3.1 and PCIe 5.1 compliant
- 80 Plus Gold certified efficiency
- Fully modular cable design
- Zero RPM low-load fan mode
Cons
- 80 Plus Gold efficiency rather than Platinum or Titanium
- 850W ceiling may not support ultra-high-wattage hardware setups
Good fit if
- You need an ATX 3.1 and PCIe 5.1 unit for current hardware.
- You are building a white-themed desktop PC.
- You want a fully modular 850W supply with 80 Plus Gold efficiency.
Skip if
- You require 1000W or higher capacity for high-draw hardware configurations.
- You prefer a standard black finish to match a dark PC chassis.
Verdict: Corsair 850W White Shift ATX PSU delivers ATX 3.1 compliance and 80 Plus Gold efficiency inside a white modular housing. It provides dependable 850W power distribution for contemporary desktop systems.
Segotep 850W ATX 3.1 Gold Power Supply
Best for: budget-focused 850W ATX 3.1 builds
- ATX Version
- ATX 3.1
- Wattage
- 850W
- Efficiency Rating
- 80 Plus Gold
- Modularity
- Fully Modular
- PCIe Connector Type
- 12VHPWR
- PCIe Version
- PCIe 5.1
View on Amazon: Segotep 850W ATX 3.1 Gold Power Supply (paid link)
The Segotep 850W ATX 3.1 Gold Power Supply is an ATX-format power supply built for modern hardware. It delivers 850W with 80 Plus Gold efficiency and complies with ATX 3.1 and PCIe 5.1 standards. You get a native 600W 12VHPWR cable, fully modular flat white cables, and a DC-DC structure with LLC resonance. It fits builds requiring up to 200% total power excursion headroom within a standard 5.91-inch chassis.
Pros
- Native 12VHPWR cable supplies up to 600W for PCIe 5.1 graphics cards
- Handles 200% total power excursion and 300% GPU power excursion
- 80 Plus Gold certified energy efficiency
- DC-DC structure with Full Bridge LLC resonance assist
Cons
- Black chassis pairs with contrasting white cables rather than matching black cables
- Maximum continuous capacity capped at 850W
Good fit if
- You need a native 600W 12VHPWR connection for a modern graphics card.
- You want flat white modular cables for easier case routing.
- You require ATX 3.1 power excursion handling up to 200%.
Skip if
- You need more than 850W of continuous power for high-draw hardware.
- You want all-black modular cables to match the casing.
Verdict: Segotep 850W ATX 3.1 Gold Power Supply delivers ATX 3.1 excursion handling and 80 Plus Gold efficiency with a dedicated 600W PCIe 5.1 interface. It offers fully modular power delivery inside a 5.91-inch chassis.
ASUS ROG Thor Titanium III 1600W ATX 3.1 PSU
Best for: ultra-high-demand systems requiring titanium-rated efficiency
- ATX Version
- ATX 3.1
- Wattage
- 1600W
- Efficiency Rating
- 80 PLUS Titanium
- Modularity
- Modular
- Warranty
- 10 Year
- Dimensions
- 7.87 × 5.91 × 3.39 inches
View on Amazon: ASUS ROG Thor Titanium III 1600W ATX 3.1 PSU (paid link)
The ASUS ROG Thor Titanium III is an ATX 3.1 power supply engineered for high-draw hardware configurations. You get an 80 Plus Titanium efficiency rating alongside 1600W of power capacity, GaN MOSFET components, and a magnetic real-time OLED power display. Its 7.87-inch frame includes double ball bearing fan cooling and an intelligent voltage stabilizer. This unit suits you if you run demanding PC systems that require high efficiency and continuous real-time power tracking.
Pros
- 80 Plus Titanium efficiency certification
- Magnetic OLED display tracks real-time power consumption
- 1600W capacity with ATX 3.1 compliance
- GaN MOSFET architecture and intelligent voltage stabilizer
- 10-year manufacturer warranty
Cons
- Chassis length of 7.87 inches requires extensive clearance
- Heavy unit weighing 6.17 pounds
Good fit if
- You need 1600W of total capacity for high-wattage components.
- You want 80 Plus Titanium efficiency and live OLED power readouts.
- You need ATX 3.1 standard compliance with an intelligent voltage stabilizer.
Skip if
- You have a compact computer chassis that cannot clear a 7.87-inch length.
- You use standard hardware that does not require 1600W capacity.
Verdict: ASUS ROG Thor Titanium III 1600W ATX 3.1 PSU pairs 80 Plus Titanium efficiency with a high 1600W ceiling for demanding setups. Its magnetic OLED display and GaN MOSFET design provide stable voltage regulation and clear real-time monitoring.
ASUS ROG Thor Platinum III 1200W PSU
Best for: high-power gaming rigs needing real-time power monitoring
- ATX Version
- ATX 3.1
- Wattage
- 1200W
- Efficiency Rating
- 80 PLUS Platinum
- Modularity
- Modular
- Warranty
- 10-year
- Recommended Use
- Gaming
View on Amazon: ASUS ROG Thor Platinum III 1200W PSU (paid link)
The ASUS ROG Thor Platinum III 1200W PSU provides 1200 watts of power under the ATX 3.1 standard with an 80 Plus Platinum efficiency rating. It features GaN MOSFET components, an aluminum enclosure, and dual-ball fan bearings. A swappable magnetic OLED display monitors real-time wattage draw in fan-up or fan-down orientations. This unit suits you if you run a high-demand gaming setup and have clearance for its 7.48-inch chassis length.
Pros
- 80 Plus Platinum efficiency rating
- Magnetic OLED display shows real-time wattage draw
- GaN MOSFETs for cooler internal operation
- Dual-ball bearing fan design
- GPU-First voltage stabilizer for graphics card delivery
Cons
- Long 7.48-inch chassis requires ample case clearance
- Substantial weight at over 5.2 pounds
Good fit if
- You want an onboard OLED screen to track real-time power consumption.
- You require 1200 watts of 80 Plus Platinum power for a high-load gaming build.
- You need a PSU with GaN MOSFETs and dual-ball fan bearings.
Skip if
- You use a compact PC case that cannot clear a 7.48-inch housing.
- You only require standard output levels such as 750W or 850W.
Verdict: ASUS ROG Thor Platinum III 1200W PSU delivers high-capacity Platinum-rated power with real-time OLED monitoring and GaN internals. It is an excellent choice if your case accommodates its 7.48-inch footprint.
Redragon 850W 80+ Gold ATX 3.1 RGB PSU
Best for: 850W builds wanting ATX 3.1 and RGB
- ATX Version
- ATX 3.1
- Wattage
- 850W
- Efficiency Rating
- 80+ Gold
- Modularity
- Fully Modular
- PCIe Connector Type
- 12V-2x6
- PCIe Version
- PCIe 5.1
View on Amazon: Redragon 850W 80+ Gold ATX 3.1 RGB PSU (paid link)
The Redragon 850W 80+ Gold ATX 3.1 RGB PSU is an 850-watt, fully modular power supply built for modern hardware. It features ATX 3.1 compliance with a dedicated PCIe 5.1 12V-2x6 cable to power current graphics cards directly. Inside, 100% Japanese capacitors and DC-to-DC circuitry maintain steady voltage, while a 9-mode RGB fan offers zero-RPM operation below 60°C. You get solid electrical specs, compact 160mm casing, and customizable case lighting.
Pros
- Native PCIe 5.1 12V-2x6 cable for direct GPU connection
- 100% Japanese capacitors with LLC resonant and DC-to-DC design
- Zero-RPM silent cooling mode when temperatures stay under 60°C
- Fully modular cabling in a 160mm deep chassis
Cons
- 80 Plus Gold efficiency rather than Platinum or Titanium
- 160mm length is slightly longer than compact 140mm units
Good fit if
- You need a dedicated 12V-2x6 connector for a modern graphics card.
- You want built-in RGB lighting effects on your power supply fan.
- You want silent operation during low loads via zero-RPM fan behavior.
Skip if
- You require an 80 Plus Platinum or Titanium efficiency tier.
- You prefer a non-lit power supply for a blackout build.
Verdict: Redragon 850W 80+ Gold ATX 3.1 RGB PSU delivers stable ATX 3.1 power and native 12V-2x6 support alongside quiet, lighted operation. It gives you modern standard compliance and modular cable routing in a 160mm chassis.
MSI MEG Ai1300P 1300W Platinum ATX 3.1 PSU
Best for: high-wattage Nvidia RTX 40 Series gaming builds
- ATX Version
- ATX 3.1
- Wattage
- 1300W
- Efficiency Rating
- 80 Plus Platinum
- Modularity
- Fully Modular
- PCIe Connector Type
- 12V-2x6
- Warranty
- 10 Year
View on Amazon: MSI MEG Ai1300P 1300W Platinum ATX 3.1 PSU (paid link)
This MSI unit delivers 1300W of continuous power with 80 Plus Platinum efficiency. It features ATX 3.1 compliance, a native 12V-2x6 connector for PCIe 5.1 hardware, and full modularity to keep your case tidy. Built with 100% Japanese 105°C capacitors and backed by a 10-year warranty, it suits your high-draw gaming build with Nvidia GeForce RTX 40 Series graphics cards when you need substantial power reserves.
Pros
- 80 Plus Platinum efficiency rating
- 1300W capacity for demanding setups
- Native 12V-2x6 connector with PCIe 5.1 support
- 100% Japanese 105°C capacitors
- 10-year warranty coverage
Cons
- 8.27-inch length requires ample case space
- 1300W output exceeds the needs of standard mid-range builds
Good fit if
- You run high-end Nvidia GeForce RTX 40 Series graphics cards.
- You need 1300W of fully modular power with 80 Plus Platinum efficiency.
- You want native PCIe 5.1 and ATX 3.1 hardware support.
Skip if
- You have a compact case unable to fit an 8.27-inch power supply.
- You build a mid-range system that does not require 1300W.
Verdict: MSI MEG Ai1300P 1300W Platinum ATX 3.1 PSU provides massive wattage, 80 Plus Platinum efficiency, and native PCIe 5.1 connectivity for power-heavy setups. It gives you reliable 105°C Japanese capacitors and long-term protection via a 10-year warranty.
MSI MPG 850W Gold ATX 3.1 Power Supply
Best for: modern 850W ATX 3.1 gaming builds
- ATX Version
- ATX 3.1
- Wattage
- 850W
- Efficiency Rating
- 80+ Gold
- Modularity
- Fully Modular
- PCIe Connector Type
- 12V-2x6
- Warranty
- 10 Year
View on Amazon: MSI MPG 850W Gold ATX 3.1 Power Supply (paid link)
This MSI unit delivers 850 watts of power with 80 Plus Gold efficiency and full ATX 3.1 compliance. It includes a native 12V-2x6 PCIe 5.1 connector for modern graphics cards and uses 100 percent Japanese 105°C capacitors for core reliability. The fully modular cabling lets you attach only the cables your chassis requires. It suits you if you need a mid-wattage power supply for a dedicated gaming setup.
Pros
- Native PCIe 5.1 12V-2x6 connector included
- 80 Plus Gold efficiency rating
- 100% Japanese 105°C capacitors
- 10-year limited warranty
- Fully modular cable design
Cons
- 850W maximum output limits high-draw multi-GPU configurations
- 80 Plus Gold efficiency is lower than Platinum or Titanium alternatives
Good fit if
- You need an ATX 3.1 power supply with a native 12V-2x6 cable for modern GPUs.
- You want fully modular cables and 100% Japanese 105°C capacitors.
- You run a gaming system requiring up to 850 watts of power.
Skip if
- You require 1000 watts or higher for extreme hardware configurations.
- You prefer a unit with an 80 Plus Platinum or Titanium efficiency rating.
Verdict: MSI MPG 850W Gold ATX 3.1 Power Supply provides 850 watts of clean power with native PCIe 5.1 support and Japanese capacitors. It offers a solid fully modular foundation backed by a 10-year warranty.
Thermaltake Toughpower GF3 1000W ATX 3.1
Best for: 1000W builds using high-draw modern GPUs
- ATX Version
- ATX 3.1
- Wattage
- 1000W
- Efficiency Rating
- 80 Plus Gold
- Modularity
- Full Modular
- PCIe Connector Type
- 12V-2x6
- Fan Size
- 135mm
View on Amazon: Thermaltake Toughpower GF3 1000W ATX 3.1 (paid link)
The Thermaltake Toughpower GF3 1000W delivers 1000W of power under ATX 3.1 and PCIe 5.1 standards. You get an 80 Plus Gold efficiency rating and a native 12V-2x6 connector that routes up to 600W to modern graphics cards. The unit features fully modular flat cabling and a 135mm cooling fan. This power supply fits high-draw builds needing strict power excursion tolerance.
Pros
- Native PCIe 5.1 12V-2x6 connector delivers up to 600W
- Meets ATX 3.1 specs for 2x total and 3x GPU power excursions
- Fully modular flat cables with visual seating check on the H++ connector
- 135mm fan handles internal heat dissipation
Cons
- 80 Plus Gold efficiency rating sits below Platinum or Titanium tiers
- 6.3-inch chassis length requires more clearance than compact 5.5-inch units
Good fit if
- You need a 1000W ATX 3.1 unit with a dedicated 600W 12V-2x6 line.
- You prefer flat, fully modular cables to simplify case routing.
- You want visual confirmation to ensure your GPU power plug is fully seated.
Skip if
- You require 80 Plus Platinum or Titanium efficiency for lower power loss.
- You have a compact case that requires a power supply shorter than 6.3 inches.
Verdict: Thermaltake Toughpower GF3 1000W ATX 3.1 gives you compliant power excursion control and 600W native GPU cabling in a standard ATX chassis. It provides dependable 80 Plus Gold efficiency and modular flat routing for high-demand hardware.
Corsair RM1000x Shift 1000W ATX 3.1 PSU
Best for: 1000W ATX 3.1 builds needing micro-fit modular cabling
- ATX Version
- ATX 3.1
- Wattage
- 1000W
- Modularity
- Fully Modular
- PCIe Version
- PCIe 5.1
- Dimensions
- 7.09 × 5.91 × 5.08 inches
- Weight
- 4.2 pounds
View on Amazon: Corsair RM1000x Shift 1000W ATX 3.1 PSU (paid link)
You get a 1000W ATX 3.1 power supply built for modern high-draw hardware with PCIe 5.1 compliance. Corsair uses Type 5 Gen 1 micro-fit modular cables that save internal space. The unit includes 105°C-rated Japanese electrolytic capacitors and Zero RPM fan mode for silent operation during low to medium loads. This unit suits you if you build a high-power system needing ATX 3.1 transient handling and compact modular wiring.
Pros
- Intel ATX 3.1 certified with PCIe 5.1 support
- Fully modular Type 5 Gen 1 micro-fit connectors
- 100% 105°C-rated Japanese electrolytic capacitors
- Zero RPM fan mode shuts off fan under low and medium loads
Cons
- Chassis length of 7.09 inches requires extra clearance in compact cases
- Uses Type 5 micro-fit connectors rather than standard-sized PSU modular interfaces
Good fit if
- You need a 1000W ATX 3.1 power supply for PCIe 5.1 hardware
- You want silent Zero RPM fan behavior during low and medium workloads
- You prefer compact micro-fit cables to reduce case clutter
Skip if
- You have a small PC case unable to fit a 7.09-inch length supply
- You need legacy full-size modular PSU cable connections
Verdict: Corsair RM1000x Shift 1000W ATX 3.1 PSU delivers 1000W with ATX 3.1 standards, Japanese capacitors, and space-saving micro-fit cables. It provides quiet low-load cooling and stable power for hardware setups requiring PCIe 5.1 compliance.
Seasonic Vertex 1200W ATX 3.1 Power Supply
Best for: high-wattage builds needing 1200W PCIe 5.1 power
- ATX Version
- ATX 3.1
- Wattage
- 1200W
- Modularity
- Full modularity
- PCIe Connector Type
- 12VHPWR
- Fan Size
- 135mm
- Efficiency Rating
- 80 Plus Gold
View on Amazon: Seasonic Vertex 1200W ATX 3.1 Power Supply (paid link)
The Seasonic Vertex 1200W ATX 3.1 Power Supply delivers 1200 watts of power with an 80 Plus Gold efficiency rating. It features full modularity and native PCIe 5.1 support via an included 12VHPWR cable. Cooling uses a 135mm Fluid Dynamic Bearing fan paired with hybrid silent control. This ATX unit suits your build if you need heavy capacity and dedicated high-wattage delivery for modern graphics cards.
Pros
- 1200W capacity with 80 Plus Gold efficiency
- Fully modular cable design
- Includes dedicated 12VHPWR cable for PCIe 5.1 support
- 135mm Fluid Dynamic Bearing fan with Hybrid Silent Fan Control
Cons
- Efficiency rated at 80 Plus Gold rather than Platinum
- ATX standard form factor does not fit small form factor cases
Good fit if
- You need 1200W of total capacity for high-draw hardware.
- You want fully modular cables and a dedicated 12VHPWR connector.
- You prefer a 135mm fluid dynamic bearing fan with hybrid silent operation.
Skip if
- You require an 80 Plus Platinum efficiency rating.
- You need a compact SFX power supply for a small enclosure.
Verdict: Seasonic Vertex 1200W ATX 3.1 Power Supply provides 1200 watts of modular power with PCIe 5.1 and ATX 3.1 compliance. It delivers high-capacity output and quiet cooling for power-heavy configurations.
Vetroo 1000W White Power Supply
Best for: high-wattage white ATX 3.1 PC builds
- ATX Version
- ATX 3.1
- Wattage
- 1000W
- Efficiency Rating
- 80 Plus Gold
- Modularity
- Full Modular
- PCIe Version
- PCIe 5.1
- Dimensions
- 5.9 × 5.5 × 3.4 inches
View on Amazon: Vetroo 1000W White Power Supply (paid link)
The Vetroo 1000W White Power Supply is a fully modular ATX power unit built for modern hardware. It delivers 1000 watts of power with 80 Plus Gold efficiency and full compliance with ATX 3.1 and PCIe 5.1 standards. Inside, it uses 105°C-rated capacitors to maintain stability under heavy loads. Measuring 5.9 by 5.5 by 3.4 inches, it fits standard ATX cases and suits you if you are planning a high-power white build.
Pros
- Native ATX 3.1 and PCIe 5.1 compliance
- 80 Plus Gold efficiency certification
- Fully modular cable setup
- Internal 105°C-rated capacitors
Cons
- 80 Plus Gold efficiency rather than Platinum or Titanium
- No silent zero-RPM fan mode listed in specifications
Good fit if
- You want a 1000W power supply in a white chassis.
- You need native ATX 3.1 and PCIe 5.1 GPU power delivery.
- You prefer fully modular cables to minimize internal clutter.
Skip if
- You require an efficiency rating higher than 80 Plus Gold.
- You need a 1000W model in black.
Verdict: Vetroo 1000W White Power Supply delivers 1000 watts of 80 Plus Gold power with full ATX 3.1 and PCIe 5.1 compatibility. It provides a fully modular layout tailored for high-output white desktop builds.
Specifications side by side
| Spec | MSI MAG 850W Fully Modular ATX Power Supply | Corsair RM850x 850W Fully Modular ATX 3.1 PSU | Corsair RM1000x 1000W ATX 3.1 PSU | Corsair RM750x Shift White 750W ATX Power Supply | Corsair RM850x Shift 850W White ATX Power Supply | Segotep 850W ATX 3.1 Gold Power Supply | ASUS ROG Thor Titanium III 1600W ATX 3.1 PSU | ASUS ROG Thor Platinum III 1200W PSU | Redragon 850W 80+ Gold ATX 3.1 RGB PSU | MSI MEG Ai1300P 1300W Platinum ATX 3.1 PSU | MSI MPG 850W Gold ATX 3.1 Power Supply | Thermaltake Toughpower GF3 1000W ATX 3.1 | Corsair RM1000x Shift 1000W ATX 3.1 PSU | Seasonic Vertex 1200W ATX 3.1 Power Supply | Vetroo 1000W White Power Supply |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Wattage | 850W | 850W | 1000W | 750W | 850W | 850W | 1600W | 1200W | 850W | 1300W | 850W | 1000W | 1000W | 1200W | 1000W |
| Efficiency Rating | 80+ Gold | Cybenetics Gold | Cybenetics Gold | 80 Plus Gold | 80 Plus Gold | 80 Plus Gold | 80 PLUS Titanium | 80 PLUS Platinum | 80+ Gold | 80 Plus Platinum | 80+ Gold | 80 Plus Gold | not specified | not specified | 80 Plus Gold |
| Modularity | Fully Modular | Fully Modular | Fully Modular | Fully Modular | Fully Modular | Fully Modular | Modular | Modular | Fully Modular | Fully Modular | Fully Modular | Full Modular | Fully Modular | Full modularity | Full Modular |
| ATX Version | ATX 3.1 | ATX 3.1 | ATX 3.1 | ATX 3.1 | ATX 3.1 | ATX 3.1 | ATX 3.1 | ATX 3.1 | ATX 3.1 | ATX 3.1, ATX 3.0 | ATX 3.1 | ATX 3.1 | ATX 3.1 | ATX 3.1, ATX 3.0 | ATX 3.1 |
| PCIe Connector Type | 12V-2x6 | 12V-2x6 | 12V-2x6 | not specified | PCIe 5.1 | 12VHPWR | not specified | not specified | 12V-2x6 | 12V-2x6 | 12V-2x6 | 12V-2x6 | not specified | 12VHPWR | not specified |
| Fan Size | not specified | not specified | not specified | 140mm | not specified | not specified | not specified | not specified | not specified | not specified | not specified | 135mm | not specified | 135mm | not specified |
| Warranty | 10 Year | not specified | not specified | not specified | not specified | not specified | 10 Year | 10-year | not specified | 10 Year | 10 Year | not specified | not specified | not specified | not specified |
| Form Factor | ATX | ATX | ATX | ATX | ATX | ATX | ATX | ATX | ATX | ATX | ATX | ATX | ATX | ATX | ATX |
| PCIe Version | PCIe 5.1 | PCIe 5.1 | PCIe 5.1 | PCIe 5.1 | PCIe 5.1 | PCIe 5.1 | not specified | not specified | PCIe 5.1 | PCIe 5.1 | PCIe 5.1 | PCIe 5.1 | PCIe 5.1 | PCIe 5.1 | PCIe 5.1 |
| Recommended Use | Gaming | not specified | not specified | not specified | not specified | not specified | not specified | Gaming | not specified | Gaming | Gaming | not specified | not specified | not specified | not specified |
| Connector | 12V-2x6 Connector | 12V-2x6 Connector | 12V-2x6 Connector | not specified | not specified | not specified | not specified | not specified | not specified | 12V-2x6 Connector | 12V-2x6 Connector | 12V-2x6 Connector | not specified | not specified | not specified |
| Size | 850W (PCIE 5) | 850W | 1000W | 750W | 850W | not specified | 1600T | not specified | 850 Watts (RGB Version) | 1300W | 850W | 1000W | 1000W | 1200W | 1000W |
| Dimensions | 12 × 8.75 × 4.92 inches | 2.3 × 3.39 × 5.91 inches | 2.3 × 3.39 × 5.91 inches | 6.3 × 5.91 × 3.39 inches | 6.3 × 5.91 × 3.39 inches | 5.91 × 5.51 × 3.35 inches | 7.87 × 5.91 × 3.39 inches | 7.48 × 5.91 × 3.39 inches | 11.8 × 7.87 × 4.72 inches | 8.27 × 6.18 × 12.9 inches | 5.91 × 5.91 × 3.39 inches | 6.3 × 5.9 × 3.4 inches | 7.09 × 5.91 × 5.08 inches | 7.3 × 13.6 × 4.5 inches | 5.9 × 5.5 × 3.4 inches |
| Weight | not specified | 3.9 pounds | 6.88 pounds | 3.75 pounds | 3.75 pounds | 5.29 pounds | 6.17 pounds | 5.22 pounds | 5.69 pounds | 3.31 pounds | 7.15 pounds | 3.95 pounds | 4.2 pounds | 7.28 pounds | not specified |
| Color | not specified | Black | Black | White | White | Black | Black | Black & Grey | white | not specified | not specified | Black | Black | not specified | 1000W-White |
| Model | not specified | not specified | not specified | CP-9020273-NA | not specified | 850W | 90YE00V1-B0NA00 | 90YE00V2-B0NA00 | 732430986 | 306-7ZP4A11-CE0 | MPG A850G PCIE 5 | PS-TPD-1000FNFAGU-4 | CP-9020253-NA | VERTEX GX-1200 | 1000G5 |
Is an ATX 3.1 Power Supply Worth It?
ATX 3.1 power supplies provide native PCIe 5.1 compatibility for contemporary desktop hardware. In daily operation, this standard pairs with dedicated 12V-2x6 GPU connectors rated up to 600W, enabling streamlined routing in modern single-GPU systems. Most ATX 3.1 models feature fully modular cabling and Japanese capacitors, delivering stable power distribution across capacities from 750W to 1600W. Selecting an ATX 3.1 unit gives your system direct compliance with modern graphics hardware specifications while maintaining clean cable management inside standard ATX enclosures.
Worth it if
- You install a modern graphics card requiring a dedicated 12V-2x6 connector or PCIe 5.1 interface.
- You build a high-output gaming system between 750W and 1600W that requires fully modular cable routing.
Skip it if
- You run legacy PC hardware that does not use PCIe 5.1 or 12V-2x6 connections.
- You use an existing power supply that already meets the wattage requirements of your current components.
If you plan to house your power supply in a Micro-ATX PC case instead, compare maximum chassis depth limits against total unit dimensions.
How We Picked These PSUs
Every power supply in this guide comes from Amazon listings that explicitly state ATX 3.1 compliance in the product title or published feature list. We verify form factor and connector data directly from manufacturer specifications. To keep options distinct for your build, we include only one size or variant from each product family. We do not physically handle or test hardware.
We order products in stock first, then by Amazon sales rank so better-selling products appear first. Live prices and inventory refresh at least daily on the page. This spec-focused layout helps you compare 15 verified ATX 3.1 power supplies for your setup in 2026.
Choosing the Right ATX 3.1 Power Supply
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Verify Physical Chassis Clearance
Check case clearance before choosing high-wattage power supplies. While standard ATX power supplies fit common mid-towers, length varies considerably across output tiers. High-capacity options like the ASUS ROG Thor Titanium III reach 7.87 inches in length. Measure your enclosure's PSU compartment, factoring in clearance for front-facing modular cables and drive cages. Shorter units around 5.9 inches offer easier cable routing in tighter spaces, whereas extended chassis depths demand dedicated cable channels and ample basement volume inside your PC case.
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Check Dedicated GPU Power Connectors
Examine the exact graphics power cables provided with the unit. ATX 3.1 units frequently include dedicated PCIe 5.1 connectors rated for up to 600W delivery over a single interface. For example, the Thermaltake Toughpower GF3 1000W includes native 12V-2x6 cabling that routes cleanly to modern high-draw expansion cards. If your graphics card utilizes this newer standard, selecting a power supply with a dedicated 12V-2x6 cable eliminates the clutter and socket strain associated with multi-plug legacy adapter splitters.
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Match Modularity to Case Layout
Evaluate the connector layout on the power supply casing. Fully modular power supplies allow you to attach only the specific cables your build requires, reducing clutter under the shroud. Specialized models like the Corsair RM750x Shift reposition the modular interface to the side panel. This side-mount configuration eases cable plugging after installation, but it requires sufficient clearance between the power supply and the side panel of your case. Choose traditional rear-facing modular plugs if your chassis lacks side-door clearance.
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Inspect Component Grade and Warranty
Review the internal component standards and manufacturer warranty coverage. Heavy gaming and sustained computational tasks place steady thermal loads on internal power components. Premium options like the MSI MEG Ai1300P feature Japanese capacitors rated for operation up to 105°C, ensuring stability under continuous workloads. Warranty lengths on ATX 3.1 supplies often extend to 10 years on high-spec platforms. Choosing a unit backed by a decade-long warranty offers practical assurance that internal hardware remains dependable through multiple future component upgrades.
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Size Total Wattage for Headroom
Calculate your system wattage to determine the ideal output capacity. Mainstream builds with single gaming cards generally run efficiently on 750W or 850W units. However, if you plan to install top-tier processors or multiple storage drives alongside high-end graphics hardware, moving to a 1200W unit like the Seasonic Vertex 1200W provides essential electrical headroom. Extra capacity prevents the power supply from operating near its maximum ceiling during load peaks, maintaining stable power delivery while leaving room for future hardware additions.
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Align Color and Build Aesthetics
Check the exterior finish and cable color when planning a visible desktop build. Most power supplies feature matte black casings, but themed builds benefit from factory-matched colorways. Options like the Vetroo 1000W White Power Supply come finished in white to integrate seamlessly with light-colored cases, motherboards, and cable sleeves. Selecting a factory-white power supply eliminates the need for aftermarket cable extensions. If your PC case features a cut-out PSU shroud, confirming the exterior finish ensures a consistent interior theme.
Frequently asked questions
What is the main difference between an ATX 3.0 and an ATX 3.1 power supply?
ATX 3.1 introduces the updated 12V-2x6 power connector alongside PCIe 5.1 compliance. This revised connector design improves mechanical contact and safety over earlier 12VHPWR implementations. In models like the Corsair RM850x and MSI MAG 850W, the 12V-2x6 interface safely delivers dedicated wattage directly to demanding graphics cards without requiring older multi-cable splitters or legacy adapters.
Can you use an ATX 3.1 power supply with older graphics cards?
Yes, you can use an ATX 3.1 power supply with older hardware. Fully modular ATX 3.1 models provide standard 8-pin and 6-pin PCIe cables alongside the dedicated 12V-2x6 interface. Power supplies such as the Thermaltake Toughpower GF3 1000W and MSI MPG 850W supply modular connections that plug directly into older graphics cards without causing electrical mismatch or configuration problems.
How much wattage do you need in an ATX 3.1 power supply?
Your wattage requirement depends on your graphics card and processor power targets. Standard single-card gaming builds run comfortably on 750W or 850W units like the Corsair RM750x Shift or Segotep 850W. If you run flagship components, choosing high-capacity units like the Corsair RM1000x or the Seasonic Vertex 1200W ensures ample headroom for sustained peak operational power draws.
What makes side-interface modular power supplies different from standard designs?
Side-interface power supplies position modular connection sockets on the side panel instead of the rear end. Units like the Corsair RM850x Shift White and RM1000x Shift use this layout alongside micro-fit connectors to simplify cable routing behind the motherboard tray. You must ensure your computer case offers adequate side clearance between the power supply compartment and side panel.
Why do some high-wattage ATX 3.1 power supplies feature GaN MOSFETs?
GaN MOSFETs provide faster switching speeds and reduced electrical energy loss compared to traditional silicon components. In high-wattage power supplies like the ASUS ROG Thor Titanium III 1600W and Platinum III 1200W, GaN architecture enables tighter voltage regulation and higher thermal efficiency. This internal hardware design helps the unit maintain stable delivery under substantial continuous computing loads.
What is the benefit of a fully modular ATX 3.1 power supply?
A fully modular ATX 3.1 unit allows you to attach only the specific cables your setup requires. Models like the Vetroo 1000W White and Redragon 850W eliminate unused wire clutter inside your chassis, which improves internal airflow and simplifies cable management. This setup also lets you route individual peripheral lines neatly through tight desktop spaces.
Are white ATX 3.1 power supplies identical in performance to black versions?
Yes, the exterior color of an ATX 3.1 power supply does not alter its electrical capabilities. White options like the Vetroo 1000W White and Corsair RM850x Shift White deliver the same 80 Plus Gold efficiency and PCIe 5.1 compatibility as black models. You choose them strictly to match the visual theme of your custom PC enclosure.