Corsair
SF-L Series SF850L Power Supply
Best compact power supply for high-performance small form factor PC builds.
The CORSAIR SF-L Series SF850L is a fully modular SFX-L power supply designed for small form factor PCs. It boasts ATX 3.1 and PCIe 5.1 compliance, ensuring compatibility with the latest hardware, including NVIDIA GeForce RTX 40 Series graphics cards. This unit features a quiet 120mm rifle bearing fan with Zero RPM mode for silent operation under light loads. Built with 100% industrial-grade, 105°C-rated Japanese capacitors, it delivers steady power output with up to 90% efficiency, earning 80 PLUS Gold and Cybenetics certifications for optimal performance and reliability.
$149.99
Owner Satisfaction
4.6
/ 5
Category Rank
230
/ 1062
#230 in Computer Power Supplies
Price vs Category Average
-84%
Below average
Wattage
850
/ W
Who it's for
- SFF enthusiasts building high-performance, space-constrained gaming rigs
- Eco-conscious users looking to minimize heat and electricity costs
- System builders prioritizing clean aesthetics and optimized internal airflow
Who should skip it
- Budget-focused builders seeking the most cost-effective power solution
- Users with ultra-compact cases requiring strict standard SFX dimensions
- Owners of large tower cases needing longer cable reach
Performance breakdown
Small Form Factor
Optimized footprint fits seamlessly into the most compact PC builds.
Future-Proof Connectivity
ATX 3.1 and PCIe 5.1 standards handle modern high-end hardware effortlessly.
Acoustic Performance
Zero RPM mode ensures near-silent operation during standard desktop tasks.
Build Reliability
Japanese capacitors provide long-term stability for demanding power-hungry components.
Cable Management
Fully modular design with micro-fit connectors simplifies tight-space cable routing.
Energy Efficiency
Gold-rated efficiency minimizes heat output and reduces overall power waste.
Key Specs
Wattage
850W
Form Factor
SFX-L
Modularity
Fully Modular
ATX Version
ATX 3.1 Certified
PCIe 5.1 12V-2x6 GPU cable included
Fan Size
120mm
Fan Bearing Type
Rifle Bearing
Zero RPM Mode Support
Yes
Features
- Compact SFX-L form factor ideal for small builds
- ATX 3.1 certified for high reliability and power efficiency
- Includes PCIe 5.1 12V-2x6 GPU cable for modern graphics cards
- Fully modular design with Type 5 micro-fit connectors for clean builds
- Quiet 120mm rifle bearing fan with Zero RPM mode
- High-quality 105°C-rated Japanese capacitors for durability
- 80 PLUS Gold and Cybenetics certified for excellent efficiency
What customers say
Customers consistently praise the Corsair SF L Series SF850L Power Supply for its exceptional build quality and thoughtful design. Its compact SFX L form factor is a significant advantage for small form factor PC builds, allowing powerful systems in confined spaces. Reviewers frequently highlight the fully modular cables as a key feature, simplifying installation and improving cable management within tight enclosures. The unit's reliable performance and quiet operation further solidify its reputation among enthusiasts seeking a premium power solution. This power supply is often considered a top choice for those prioritizing both space efficiency and dependable power delivery.
Know before you buy
The SFX-L form factor is slightly longer than a standard SFX power supply, allowing it to house a larger 120mm fan. This provides better cooling and quieter operation while still fitting into compact small form factor cases that support the SFX-L standard.
Yes. The SF850L is ATX 3.1 and PCIe 5.1 compliant and includes a dedicated 12V-2x6 GPU cable, allowing you to power modern high-performance graphics cards directly without needing bulky adapters.
The Zero RPM mode allows the 120mm fan to remain completely off during low to medium loads. This ensures silent operation when you are performing light tasks, with the fan only spinning up automatically when the power supply temperature increases under heavier workloads.
No. The SF850L uses Corsair Type 5 micro-fit connectors, which are smaller and have a different pinout than previous generations. You must use the cables included in the box to ensure safety and compatibility.
Japanese capacitors rated for 105°C are industry-standard for high-end power supplies. They offer superior heat resistance and long-term reliability compared to lower-grade components, ensuring the unit maintains stable power delivery over many years.
This certification confirms that the power supply operates at a minimum of 90% efficiency at 50% load. High efficiency reduces the amount of wasted energy as heat, which is particularly important in the confined spaces of small form factor PC cases.
Still have a question?
Ask Hayley anything about this product before you decide.
Ready to buy?
$150