Antec CSK850 PRO Semi-Modular ATX 3.1 PSU 850W 80 Plus Bronze
The Antec CSK850 PRO is a robust 850W power supply unit engineered to meet the rigorous demands of...The Antec CSK850 PRO is a robust 850W power supply unit engineered to meet the rigorous demands of modern gaming systems and high-performance workstations. Built to the latest ATX 3.1 standards, this semi-modular PSU is specifically designed for future-proofing, offering native PCIe 5.1 support via a high-capacity 12V 2x6 connector capable of delivering up to 600W to the newest graphics cards. By utilising a semi-modular cable design, the unit allows builders to use only the necessary peripheral cables, which significantly improves internal cable management and overall chassis airflow. Reliability and safety are at the forefront of the CSK850 PRO design. It features 80 Plus Bronze certification, achieving up to 90 per cent efficiency to ensure minimal energy waste and cooler operation. The unit is protected by Antec's CircuitShield suite, an industrial-grade set of eight protections that safeguard against issues such as over-voltage and short circuits. For cooling, a 120 mm silent fan with intelligent thermal control is used. This PSU ensures reliable, efficient, and safe power delivery. Its compact design and semi-modular cables make installation easy and improve system airflow. Backed by a 5-year warranty, it is a future-proof choice for demanding PC builds. Full Specifications Model: CSK850 PRO MPN: 0-761345-20071-4 Form Factor: ATX 12V 3.1 semi-modular Wattage: 850 W continuous Efficiency: 80 Plus Bronze (up to ~90%) ATX Standard: ATX 3.1 PCIe Support: PCIe 5.1 native 12V 2x6 GPU connector Protection Features (CircuitShield™): OCP, OVP, UVP, SCP, OPP, OTP, SIP, NL Cooling: 120 mm silent fan with thermal manager fan speed control PFC: Active PFC Power Good Signal: 100–150 ms Input Voltage: 200–240 V AC, 12 A max, 50–60 Hz Dimensions (L x W x H): 140 x 150 x 86 mm Net Weight: Approximately 1.95 kg Connectors: 1 x 24-pin ATX main, 1 x 16-pin (12+4) PCIe 5.1 (12VHPWR, up to 600 W), 2 x 8-pin (4+4) CPU EPS, 4 x 8-pin (6+2) PCIe, 6 x SATA, 3 x Molex Operating Temperature: 0–40 °C Certifications: TUV, CB, RCM, CE, BIS, UKCA, KC Warranty: 5 years.
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Product Information
Full details
The Antec CSK850 PRO is an 850W semi-modular power supply unit designed for PC builders seeking robust power delivery and future-proofing. Its key benefit is ATX 3.1 and PCIe 5.1 readiness, ensuring compatibility with the latest high-power GPUs. A potential caveat is its 80 Plus Bronze efficiency rating, which is good but not as high as Gold or Platinum rated PSUs for maximum energy savings.
All features
Model Part Number
0-761345-20071-4
Brand
Antec
Extended Product Information
FAQs
What is ATX 3.1 and why is it important?
ATX 3.1 is the latest power supply standard that enhances support for high-transient power excursions from modern GPUs, ensuring system stability. It also standardizes the 12V 2x6 (12VHPWR) connector for PCIe 5.1 graphics cards.
Is this PSU compatible with 110V power outlets?
No, the Antec CSK850 PRO requires an input voltage of 200-240V AC. It is not designed for regions that exclusively use 110-120V power without a voltage converter.
How do I connect the PCIe 5.1 GPU?
Use the dedicated 16-pin (12+4) PCIe 5.1 (12V 2x6) connector that comes with the PSU. Connect one end to the graphics card and the other to the PSU's modular port labeled for this connection.
What does 'semi-modular' mean?
Semi-modular means that some essential cables (like the ATX 24-pin and CPU power) are permanently attached to the power supply, while others (like PCIe, SATA, and Molex) are detachable. This offers a balance between ease of use and cable management flexibility.
How often should I clean the power supply?
It's recommended to clean the dust from the PSU's exterior and fan grille every 3-6 months, depending on your environment's dust levels, to maintain optimal cooling and efficiency.
What is included in the CircuitShield™ protection suite?
The CircuitShield™ suite includes Over Current Protection (OCP), Over Voltage Protection (OVP), Under Voltage Protection (UVP), Short Circuit Protection (SCP), Over Power Protection (OPP), Over Temperature Protection (OTP), Surge and Inrush Current Protection (SIP), and No Load Operation (NL).
What is the warranty period for this PSU?
The Antec CSK850 PRO comes with a 5-year manufacturer's warranty.
Troubleshooting
PC does not power on.
Verify that the PSU power switch is in the 'On' position. Ensure the main power cable is securely connected to both the PSU and the wall outlet. Check that all internal power cables are firmly seated in their respective motherboard and component connectors.
System shuts down unexpectedly during heavy load.
Check if the system's total power draw exceeds the PSU's 850W capacity. Ensure the PSU is receiving adequate ventilation and is not overheating. Verify all power connections are secure.
Fans are unusually loud.
The fan speed increases with load and temperature. If loud at idle, ensure the fan intake is clear of dust and obstructions. If the issue persists, contact support.
Components are not receiving power.
Double-check the modular cable connections. Ensure the correct cables are used for the intended components (e.g., PCIe for GPU, SATA for drives). Try reseating the modular cables on the PSU side as well.
Pros and Cons
Pros
Supports the latest ATX 3.1 and PCIe 5.1 standards for next-generation hardware.
Semi-modular design simplifies cable management and improves airflow.
Comprehensive suite of safety protections (CircuitShield™) ensures component safety.
Quiet operation thanks to the 120 mm silent fan with thermal control.
Reliable power delivery for high-performance systems.
Comes with a 5-year warranty for user confidence.
Cons
80 Plus Bronze efficiency is good but less efficient than higher-tier ratings (Gold, Platinum).
Requires a 200-240V AC input voltage, limiting compatibility in regions with different power standards (e.g., 110-120V without a converter).
Only one native PCIe 5.1 12V 2x6 connector is included, though other PCIe connectors are available.
Non-fully modular design means some essential cables are permanently attached.
Setup, Compatibility & Care
Setup:
Ensure your system's power requirements do not exceed 850W.
Connect the necessary modular cables (ATX 24-pin, CPU EPS, PCIe, SATA, Molex) to the PSU and your motherboard/components.
Install the PSU securely into your PC case using the provided screws.
Connect the main power cord to the PSU and a suitable wall outlet.
Compatibility:
Form Factor: ATX 12V 3.1
Input Voltage: Requires 200-240V AC input. Ensure your region's power supply matches this requirement.
Connectors: Includes standard ATX, CPU, PCIe (including one 12V 2x6 for PCIe 5.1), SATA, and Molex connectors for most modern components.
Care:
Cleaning: Periodically dust the exterior of the PSU and the fan grille using a soft brush or compressed air. Never spray liquids directly onto the unit.
Ventilation: Ensure the PSU's fan intake (usually at the bottom or rear of the case) is not obstructed to allow for proper airflow and cooling.
Environment: Operate within the specified temperature range of 0–40 °C.
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