Corsair SF850 850W Platinum SFX Alternatives: 6 Similar Picks Compared
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The Corsair SF850 850W Platinum SFX Power Supply delivers high power density in a compact form factor. It supports ATX 3.1 and PCIe 5.1 standards for modern graphics cards. If you are looking for corsair sf850 alternatives, you might want a different size or efficiency rating. This guide compares 6 similar power supplies based on their published specifications.
The original unit excels in small-form-factor builds due to its SFX dimensions. However, you may prefer standard ATX sizes for better airflow or easier installation. Some users need higher wattage for extreme workloads. Others might prioritize Gold efficiency over Platinum for cost reasons. We selected these alternatives because their specs overlap with the original. This list covers fully modular units with ATX 3.1 compliance. You can compare wattage, dimensions, and connector standards to find the right fit for your case.
How each alternative compares
MSI MAG 1250W Gold Power Supply
The MSI MAG 1250W Gold Power Supply offers significantly more wattage than the Corsair SF850. It provides 1250W compared to the SF850’s 850W, making it better for high-end builds. However, it uses a standard ATX form factor instead of the compact SFX size. This means it will not fit in small cases. It also has Gold efficiency rather than Platinum. You should choose this if you have a mid-tower case and need extra power headroom for future upgrades. The 10-year warranty matches high-end expectations.
Enermax Revolution III 1000W ATX 3.1 PSU
The Enermax Revolution III 1000W ATX 3.1 PSU provides 1000W of power, which is higher than the Corsair SF850’s 850W. It is designed for larger ATX cases rather than compact SFX builds. The efficiency is Gold, which is one tier below the SF850’s Platinum rating. You give up the compact size and higher efficiency for more raw power output. This unit is ideal for standard desktop builds where space is not a constraint. It supports PCIe 5.1 for modern graphics cards. Pick this if you prioritize wattage over form factor.
ASRock Steel Legend 1200W Platinum PSU
The ASRock Steel Legend 1200W Platinum PSU matches the Corsair SF850’s Platinum efficiency rating but delivers 1200W of power. It is a full-size ATX unit, so it lacks the compact SFX footprint of the SF850. This makes it unsuitable for small-form-factor PCs. You gain 350W of extra power and a 10-year warranty. The unit is heavier and larger. Choose this alternative if you are building in a standard ATX case and need maximum power density with top-tier efficiency. It supports ATX 3.1 and PCIe 5.1 standards.
MSI MAG 1200W Platinum Modular PSU
The MSI MAG 1200W Platinum Modular PSU offers 1200W of power, exceeding the Corsair SF850’s 850W. It shares the same Platinum efficiency rating. Like the SF850, it supports ATX 3.1 and PCIe 5.1. However, it is a standard ATX size, not the compact SFX form factor. You trade the small footprint for significantly higher wattage. This unit is heavier and requires more space inside your case. It is best for users who need high power for extreme gaming or workstation tasks in a standard tower. It includes a 10-year warranty.
MSI MAG 850W Fully Modular ATX Power Supply
The MSI MAG 850W Fully Modular ATX Power Supply matches the Corsair SF850’s 850W wattage. However, it uses Gold efficiency instead of Platinum. It is a standard ATX unit, so it does not fit in small SFX cases. You gain a 10-year warranty and standard ATX compatibility. The efficiency difference means slightly more heat waste under load. This is a practical choice for standard gaming builds where case size is not an issue. It supports PCIe 5.1 and ATX 3.1 standards. Pick this if you want a reliable mid-range option with a long warranty.
Corsair RM850x Shift 850W White ATX Power Supply
The Corsair RM850x Shift 850W White ATX Power Supply provides the same 850W wattage as the SF850. It features Gold efficiency, which is one step below the SF850’s Platinum rating. It is a full-size ATX unit, so it lacks the compact SFX dimensions. You gain a standard form factor and a white color option. The unit is lighter than the SF850 but requires more space. It supports ATX 3.1 and PCIe 5.1. Choose this if you are building in a standard ATX case and prefer Gold efficiency with Corsair reliability. It is a solid mid-range choice.
Quick picks
Our 7 picks
Corsair SF850 850W Platinum SFX Power Supply
Best for: small-form-factor high-efficiency builds
- Wattage
- 850 Watts
- Efficiency Rating
- 80 PLUS Platinum
- Modularity
- Fully Modular
- ATX Version
- ATX 3.0
- Fan Size
- 92mm
- PCIe Version
- PCIe 5.1
View on Amazon: Corsair SF850 850W Platinum SFX Power Supply
The Corsair SF850 is a fully modular ATX 3.0 power supply in a compact SFX form factor. It delivers 850 watts of 80 PLUS Platinum efficiency, making it ideal for high-performance small-form-factor builds. The unit supports ATX 3.0 and PCIe 5.0 standards, handling modern GPU power demands. Its 92mm fan and Japanese capacitors ensure reliable operation in tight spaces where space and power density matter most.
Pros
- 80 PLUS Platinum efficiency rating
- Compact SFX form factor
- ATX 3.0 compliant with PCIe 5.0 support
- Fully modular with Type-5 Micro-Fit connectors
Cons
- Smaller 92mm fan may run louder under load
- Limited to 850W output compared to larger ATX units
- SFX size restricts compatibility with some standard cases
Good fit if
- You are building a small-form-factor PC
- You need high efficiency in a compact size
- You require ATX 3.0 compatibility for new GPUs
Skip if
- You need more than 850W of power
- You are using a standard ATX case without SFX support
- You prefer larger fans for silent operation
Verdict: Corsair SF850 850W Platinum SFX is the best overall choice for small-form-factor builds needing high power density. It fits users who prioritize compact size and modern PCIe 5.0 support over raw wattage.
MSI MAG 1250W Gold Power Supply
Best for: High-wattage standard ATX gaming builds
- Wattage
- 1250W
- Efficiency Rating
- 80+ Gold
- Modularity
- Fully Modular
- ATX Version
- ATX 3.1
- PCIe Connector Type
- 12V-2x6
- Warranty
- 10 Year
This is a fully modular ATX 3.1 power supply rated for 1250W. It carries an 80 Plus Gold efficiency rating and includes PCIe 5.1 support with a 12V-2x6 connector. The unit measures 11.5 by 9.25 by 5 inches and weighs 7.25 pounds. It is designed for high-end gaming builds that require significant power headroom and modern connector standards.
Pros
- 1250W output capacity
- 80 Plus Gold efficiency
- ATX 3.1 and PCIe 5.1 ready
- 10-year limited warranty
Cons
- 80 Plus Gold rating is lower than the Platinum options on this list
- Standard ATX form factor is bulkier than the SFX units it replaces
- Heavier at 7.25 pounds compared to compact alternatives
Good fit if
- You need maximum wattage for future GPU upgrades
- You are building a standard ATX case
- You want a 10-year warranty
Skip if
- You are building a small form factor PC
- You need 80 Plus Platinum efficiency
- You prefer the lowest weight possible
Verdict: MSI MAG A1250GL 1250W Gold ATX 3.1 provides ample power for enthusiasts who prioritize capacity over compact size. It suits users building in standard mid-tower cases who need reliable support for next-generation graphics cards.
Enermax Revolution III 1000W ATX 3.1 PSU
Best for: high-wattage ATX builds
- Wattage
- 1000 W
- Efficiency Rating
- 80 PLUS Gold
- Modularity
- Full Modular
- ATX Version
- ATX 3.1
- PCIe Connector Type
- 12V-2x6
- Fan Size
- 120 mm
The Enermax Revolution III is a 1000W fully modular power supply built for high-end systems. It carries an 80 PLUS Gold efficiency rating and supports ATX 3.1 standards with PCIe 5.1 compatibility. The unit includes a 12V-2x6 connector capable of delivering 600W for modern GPUs. It features a whisper-quiet fan and mesh cables for clean routing. This model suits users needing extra headroom for power-hungry components.
Pros
- 1000W output capacity
- 80 PLUS Gold efficiency
- ATX 3.1 and PCIe 5.1 support
- 600W 12V-2x6 cable capability
- Fully modular design
Cons
- Gold efficiency is lower than Platinum competitors
- Standard ATX size may not fit small cases
- Heavier at 4.19 pounds
Good fit if
- You need 1000W for extreme overclocking
- You want PCIe 5.1 native support
- You prioritize efficiency over compact size
Skip if
- You require a small SFX form factor
- You need Platinum efficiency certification
- You want a lighter power supply
Verdict: Enermax Revolution III 1000W ATX 3.1 delivers robust power for large builds. It fits users who prioritize high wattage and modern connector standards over compact dimensions.
ASRock Steel Legend 1200W Platinum PSU
Best for: high-wattage ATX builds needing extra headroom
- Wattage
- 1200W
- Efficiency Rating
- 80 Plus Platinum, Cybenetics Platinum
- Modularity
- Fully Modular
- ATX Version
- ATX 3.1
- PCIe Connector Type
- 12V-2x6
- Fan Size
- 135mm
The ASRock Steel Legend SL-1200P is a 1200W ATX 3.1 power supply built for high-end gaming rigs and workstations. It features 80 Plus Platinum efficiency and a fully modular design. The unit includes a large 135mm fan and native 12V-2x6 connectors for next-gen GPUs. It suits builders who need extra wattage headroom for multi-GPU setups or heavy overclocking.
Pros
- 1200W output for extreme gaming and workstation loads
- 80 Plus Platinum and Cybenetics Platinum efficiency
- ATX 3.1 and PCIe 5.1 ready with 12V-2x6 connector
- 135mm FDB fan with intelligent iCool control
- 10-year warranty coverage
Cons
- Large 1200W size may not fit compact cases
- Standard ATX form factor limits small build options
- Higher wattage may be unnecessary for single-GPU systems
Good fit if
- You need 1200W for multi-GPU or workstation builds
- You want Platinum efficiency to reduce heat and noise
- You are building a standard ATX case with ample space
Skip if
- You are building a small form factor (SFF) PC
- You only need 850W for a single high-end GPU
- You prefer SFX or SFX-L power supply sizes
Verdict: ASRock Steel Legend SL-1200P 1200W delivers robust power for users who demand extra headroom for extreme gaming or workstation tasks. It fits best in standard ATX cases where size is not a constraint.
MSI MAG 1200W Platinum Modular PSU
Best for: High-end gaming builds needing 1200W
- Wattage
- 1200W
- Efficiency Rating
- 80 PLUS Platinum
- Modularity
- Fully Modular
- ATX Version
- ATX 3.1
- PCIe Connector Type
- 12V-2x6
- Fan Size
- 135 mm
This 1200W ATX 3.1 power supply delivers high efficiency with 80 Plus Platinum certification. It features a native 12V-2x6 connector for PCIe 5.1 GPUs and includes real-time current protection via GPU Safeguard. The compact 150 mm form factor fits most cases, and the 135 mm fan ensures durability. It suits users needing extra headroom for high-end hardware.
Pros
- 1200W output capacity
- 80 Plus Platinum efficiency
- Native 12V-2x6 connector
- 10-year warranty
- Compact 150 mm size
Cons
- Heavier at 7.5 pounds
- Larger than SFX alternatives
- No app control mentioned
Good fit if
- You need 1200W for future GPU upgrades
- You want 80 Plus Platinum efficiency
- You prefer a compact ATX form factor
Skip if
- You require SFX or SFX-L dimensions
- You need a fully silent operation mode
- You prefer a lower wattage unit
Verdict: MSI MAG A1200PLS 1200W ATX 3.1 fits builders who need high wattage and efficiency in a compact ATX case. It is ideal for those planning to use next-generation PCIe 5.1 graphics cards.
MSI MAG 850W Fully Modular ATX Power Supply
Best for: Standard ATX gaming builds needing PCIe 5.1
- Wattage
- 850W
- Efficiency Rating
- 80+ Gold
- Modularity
- Fully Modular
- ATX Version
- ATX 3.1
- PCIe Connector Type
- 12V-2x6
- Warranty
- 10 Year
This is an 850W fully modular power supply built for gaming systems. It meets the ATX 3.1 standard and includes PCIe 5.1 support with a 12V-2x6 connector. You get 80 Plus Gold efficiency for reliable power delivery. The unit measures 12 inches long and weighs 850W capacity. It comes with a 10-year warranty for long-term peace of mind.
Pros
- 80 Plus Gold efficiency rating
- ATX 3.1 and PCIe 5.1 ready
- Includes 12V-2x6 connector
- Fully modular cable design
- 10-year warranty coverage
Cons
- 80 Plus Gold rating is lower than Platinum competitors
- 12-inch length is bulkier than SFX alternatives
- Standard ATX form factor limits small case compatibility
Good fit if
- You need PCIe 5.1 support for modern GPUs
- You want a fully modular ATX unit
- You prefer a 10-year warranty period
Skip if
- You require 80 Plus Platinum efficiency
- You are building in a small form factor case
- You need an SFX power supply
Verdict: MSI MAG A850GL 850W Gold ATX 3.1 offers solid Gold efficiency and modern PCIe 5.1 support for standard ATX cases. It is a practical pick for gamers who prioritize warranty length and connector compatibility over compact size or higher efficiency tiers.
Corsair RM850x Shift 850W White ATX Power Supply
Best for: Standard ATX cases needing Gold efficiency
- Wattage
- 850W
- Efficiency Rating
- 80 Plus Gold
- Modularity
- Fully Modular
- ATX Version
- ATX 3.1
- 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
The Corsair RM850x Shift is a fully modular ATX 3.1 power supply rated at 850W. It carries an 80 Plus Gold efficiency rating and supports PCIe 5.1 for modern graphics cards. The unit measures 6.3 by 5.91 by 3.39 inches and weighs 3.75 pounds. It is available in white. This model suits builders who need a standard ATX form factor with high efficiency and recent connector standards.
Pros
- 80 Plus Gold efficiency rating
- Fully modular cable design
- Supports ATX 3.1 standard
- Includes PCIe 5.1 connectors
Cons
- 80 Plus Gold rating is lower than Platinum competitors
- Standard ATX size is larger than SFX options
- White color may not match black builds
Good fit if
- You need a standard ATX form factor
- You want 80 Plus Gold efficiency
- You are building a white-themed PC
Skip if
- You require a compact SFX form factor
- You need 80 Plus Platinum efficiency
- You prefer a black color scheme
Verdict: Corsair RM850x Shift 850W Gold is a solid mid-range choice for standard ATX cases. It fits users who prioritize efficiency and modern PCIe standards over compact size.
Specifications side by side
| Spec | Corsair SF850 850W Platinum SFX Power Supply | MSI MAG 1250W Gold Power Supply | Enermax Revolution III 1000W ATX 3.1 PSU | ASRock Steel Legend 1200W Platinum PSU | MSI MAG 1200W Platinum Modular PSU | MSI MAG 850W Fully Modular ATX Power Supply | Corsair RM850x Shift 850W White ATX Power Supply |
|---|---|---|---|---|---|---|---|
| Wattage | 850 Watts | 1250W | 1000 W | 1200W | 1200W | 850W | 850W |
| Efficiency Rating | 80 PLUS Platinum | 80+ Gold | 80 PLUS Gold | 80 Plus Platinum, Cybenetics Platinum | 80 PLUS Platinum | 80+ Gold | 80 Plus Gold |
| Modularity | Fully Modular | Fully Modular | Full Modular | Fully Modular | Fully Modular | Fully Modular | Fully Modular |
| ATX Version | ATX 3.0 | ATX 3.1 | ATX 3.1 | ATX 3.1 | ATX 3.1 | ATX 3.1 | ATX 3.1 |
| PCIe Connector Type | not specified | 12V-2x6 | 12V-2x6 | 12V-2x6 | 12V-2x6 | 12V-2x6 | PCIe 5.1 |
| Fan Size | 92mm | not specified | 120 mm | 135mm | 135 mm | not specified | not specified |
| Warranty | not specified | 10 Year | not specified | 10 Years | 10 Year | 10 Year | not specified |
| Form Factor | 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 | PCIe 5.1 |
| Recommended Use | not specified | Gaming | not specified | not specified | Gaming | Gaming | not specified |
| Connector | not specified | 12V-2x6 Connector | not specified | not specified | 12V-2x6 Connector | 12V-2x6 Connector | not specified |
| Size | 850 Watts | not specified | 1000W | 1200W | 3.4" x 5.9" x 5.9" | 850W (PCIE 5) | 850W |
| Dimensions | 4.92 × 3.94 × 2.5 inches | 11.5 × 9.25 × 5 inches | 5.51 × 5.91 × 3.39 inches | 5.91 × 5.91 × 3.39 inches | 11.9 × 8.86 × 5.08 inches | 12 × 8.75 × 4.92 inches | 6.3 × 5.91 × 3.39 inches |
| Weight | 2.31 pounds | 7.25 pounds | 4.19 pounds | not specified | 7.28 pounds | not specified | 3.75 pounds |
| Color | Black | Black | Black | not specified | Information Not Available | not specified | White |
| Model | CP-9020256-NA | MAGA1250GLPCIE5 | ERV1000G-AHG-MAC | 90-UXS120-PFUAAA | MAGA1200PLSPCIE5 | not specified | not specified |
If you need a larger chassis for your build, compare corsair 4000d rs frame modular alternatives to verify component clearances.
Frequently asked questions
Is there a smaller alternative to the Corsair SF850 for tiny cases?
The Corsair SF850 is already an SFX form factor, which is one of the smallest standard sizes for high-wattage units. Most alternatives listed here use standard ATX dimensions. You will need a mid-tower or full-tower case to fit these larger units, as they measure over 5 inches in width compared to the SF850’s 3.94 inches.
Which alternative offers the highest wattage for extreme builds?
The ASRock Steel Legend 1200W Platinum PSU provides the highest wattage on this list at 1200W. It is designed for users who need extra headroom for extreme gaming or workstation tasks. This unit supports ATX 3.1 and PCIe 5.1 standards, ensuring compatibility with the latest high-power graphics cards without bottlenecking performance.
Do these alternatives support the latest PCIe 5.1 graphics cards?
Yes, all listed alternatives support PCIe 5.1 standards. This includes the MSI MAG 1250W Gold, Enermax Revolution III 1000W, and ASRock Steel Legend 1200W units. They also adhere to ATX 3.1 specifications, which ensures proper power delivery for next-generation GPUs. This makes them suitable for modern high-end gaming rigs.
Is there a more efficient option than the 850W Gold models?
The ASRock Steel Legend 1200W and MSI MAG 1200W Platinum PSUs offer 80 Plus Platinum efficiency ratings. These are more efficient than the Gold-rated models like the MSI MAG 1250W or Enermax Revolution III. Platinum certification means less energy is wasted as heat, which can improve system stability and reduce operating temperatures in your build.
Which alternative is best for a standard ATX mid-tower case?
The MSI MAG 1250W Gold Power Supply is ideal for standard ATX mid-tower cases. It provides 1250W of power, which is significantly more than the SF850’s 850W. Its larger dimensions make it unsuitable for small cases, but it fits perfectly in standard builds where you prioritize raw capacity and reliable support for next-generation graphics cards.
Are there fully modular options available in these alternatives?
All seven alternatives listed are fully modular. This includes the Corsair RM850x Shift, MSI MAG series, Enermax Revolution III, and ASRock Steel Legend. Fully modular designs allow you to connect only the cables you need, which helps with cable management. This feature is consistent across both Gold and Platinum efficiency tiers in this group.