Corsair
RMx Series RM850x
Best high-performance power supply for quiet, reliable custom PC builds.
The CORSAIR RM850x is a fully modular power supply designed for efficient and quiet PC operation. It delivers 850 Watts of 80 PLUS Gold certified power, ensuring high efficiency and reliability. Built with 100% Japanese 105°C capacitors, it guarantees unwavering power delivery and long-term durability. The PSU features a specially tuned fan curve for minimal noise and a Zero RPM fan mode that completely switches off the fan at low to medium loads for silent performance. Its fully modular design allows for cleaner builds by only connecting necessary cables.
$108.99
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Owner Satisfaction
4.6
/ 5
Category Rank
197
/ 1062
#197 in Computer Power Supplies
Price vs Category Average
-88%
Below average
EPS Connector
2
Who it's for
- System builders prioritizing long-term hardware stability and longevity
- Quiet-computing enthusiasts working in shared or home office spaces
- PC builders aiming for clean aesthetics and improved internal airflow
Who should skip it
- Budget-conscious shoppers looking for entry-level power supply options
- Users building in compact or small form factor PC cases
- Builders who prioritize easy cable routing and flexible management
Performance breakdown
Power Efficiency
80 PLUS Gold certification ensures minimal energy waste during heavy system loads.
Acoustic Performance
Zero RPM mode keeps your workspace silent during light computing tasks.
Build Reliability
Premium Japanese capacitors provide long-term stability for high-end gaming rigs.
Cable Management
Fully modular design simplifies installation and keeps your case interior tidy.
Component Longevity
A decade-long warranty reflects exceptional engineering and confidence in internal parts.
System Compatibility
Standard ATX form factor fits seamlessly into most modern desktop builds.
Key Specs
EPS Connector
2
SATA Connector
10
Fan Bearing Technology
Rifle Bearing
Dimensions
150mm x 86mm x 160mm
Modularity
Fully Modular
PSU Compatibility
ATX12V v2.4 and EPS12V 2.92 standards
Cable Type
Low-Profile, All Black
Floppy Connector
1
Features
- Delivers 850W of 80 PLUS Gold efficient power.
- Virtually silent operation with a specially tuned fan curve.
- Zero RPM fan mode for complete silence at low to medium loads.
- 100% Japanese 105°C capacitors for exceptional reliability.
- Fully modular cables for easier building and better airflow.
- Low-profile, all-black cables for a clean aesthetic.
What customers say
Customers consistently praise the Corsair RM850x for its exceptional reliability and high build quality. Many users highlight its consistent performance and quiet operation, making it a dependable choice for various PC builds. The fully modular cables are frequently mentioned as a significant convenience, simplifying installation and cable management. Users appreciate the peace of mind that comes with a power supply known for its robust construction and long term stability, affirming its position as a top tier component.
Know before you buy
The Zero RPM mode allows the 140mm fan to remain completely stationary during low to medium power loads. This ensures the power supply operates in total silence when you are performing light tasks like web browsing or document editing.
Yes, the RM850x is fully modular, meaning every cable can be detached from the unit. This is ideal for cable management, as you only need to plug in the specific cables required for your components, resulting in a cleaner interior and improved airflow.
The RM850x follows the standard ATX form factor with dimensions of 150mm x 86mm x 160mm. It is compatible with the vast majority of mid-tower and full-tower cases, but you should verify that your specific case supports a 160mm deep power supply.
This unit is built with 100% Japanese 105°C capacitors, which are industry-standard components known for their high heat tolerance and longevity. These parts contribute to the unit's 100,000-hour MTBF rating and are backed by a 10-year warranty.
With 6 PCIe connectors and 10 SATA connectors, the RM850x is well-equipped for most high-end builds, including those with multiple storage drives or power-hungry graphics cards. It also includes two EPS connectors to support high-performance motherboards.
The 80 PLUS Gold rating indicates that this power supply is at least 87% to 90% efficient under various load conditions. Higher efficiency means less power is wasted as heat, which can lead to lower electricity costs and a cooler-running system.
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