Corsair
SF Series SF850 Fully Modular 80 PLUS Platinum SFX Power Supply
Best high-wattage power supply for compact, high-performance PC builds.
The Corsair SF850 Platinum is a top-tier Small Form Factor (SFF) Power Supply Unit engineered for high-performance gaming rigs and reliable workstations. This unit delivers exceptionally clean and efficient power delivery, maximizing system performance while minimizing energy waste due to its 80 PLUS Platinum rating. Designed specifically for compact builds, it utilizes the SFX form factor, making it ideal for smaller cases where space is limited. The fully modular cabling system significantly simplifies the building process and improves internal airflow. This model provides a robust 850W of continuous power, ensuring stability for demanding components.
$224.99
Owner Satisfaction
4.8
/ 5
Category Rank
8
/ 1062
#8 in Computer Power Supplies
Price vs Category Average
-76%
Below average
Wattage
850
/ W
Who it's for
- Small form factor builders needing high-end power
- Eco-conscious users seeking lower energy bills
- Quiet-focused builders prioritizing long-term reliability
Who should skip it
- Budget-conscious builders comparing against standard ATX units
- Noise-sensitive users running high-load systems
- Standard ATX case owners needing longer cable reach
Performance breakdown
Power Density
Unmatched wattage output packed into a remarkably small footprint.
Energy Efficiency
Platinum certification ensures minimal heat waste during intensive gaming sessions.
Cable Management
Fully modular design makes routing cables in tight cases effortless.
Build Quality
Premium internal components provide rock-solid stability for high-end hardware.
Compatibility
Standard SFX sizing fits perfectly in almost any compact chassis.
Thermal Performance
Efficient power conversion keeps internal temperatures low under heavy loads.
Key Specs
Wattage
850W
Form Factor
SFX
Modularity
Fully Modular
Efficiency Rating
80 PLUS Platinum
Model Number
CP-9020256-NA
Features
- Fully modular design simplifies cable management
- Achieves 80 PLUS Platinum efficiency rating
- Compact SFX form factor for small builds
- Provides 850W of continuous power output
- Ensures stable, clean power delivery
- Ideal for high-performance SFF systems
What customers say
The Corsair SF850 is highly regarded for its exceptional power density, delivering 850W within a compact SFX design ideal for high-performance Small Form Factor builds. Users value the 80 PLUS Platinum efficiency, which contributes to quieter operation, especially with the effective zero RPM fan mode during lighter use. Build quality and reliability receive consistent praise, supported by a strong warranty. The fully modular nature greatly aids clean cable management in tight spaces. While the premium price is noted, the consensus is that the unmatched power delivery and efficiency justify the cost, making it a top choice for demanding SFF system integrators.
Know before you buy
Yes. While the SF850 is designed for compact SFX cases, it includes an adapter bracket that allows it to be mounted in standard ATX cases as well.
The 80 PLUS Platinum rating indicates that the power supply is highly efficient, converting at least 92% of AC power into DC power at 50% load. This efficiency reduces wasted energy as heat, which can lead to lower electricity costs and a cooler-running system over time.
Yes, the SF850 is fully modular, meaning every cable can be detached from the unit. This is a major advantage in small form factor builds, as it allows you to use only the cables you need, significantly reducing clutter and improving airflow inside tight spaces.
850W is plenty for most high-performance gaming rigs, including those with top-tier CPUs and modern graphics cards. However, you should always check the recommended power requirements for your specific GPU and CPU combination to ensure it meets your total system draw.
Yes, the unit includes a full set of modular cables tailored for compact builds. Because it is designed for SFF cases, the included cables are typically shorter than those found in standard ATX power supplies to prevent excess cable bunching.
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