Enermax ERV650G-AHG-NAC
Enermax CYBERG II 650W ATX 3.1 Power Supply User Manual
Model: ERV650G-AHG-NAC
1. Introduction
This manual provides detailed instructions for the installation, operation, and maintenance of your Enermax CYBERG II 650W Non-Modular ATX 3.1 Power Supply. The CYBERG II series is designed to deliver stable and efficient power to your desktop PC components, featuring PCIe 5.1 readiness, 80 Plus Gold efficiency, and durable Japanese capacitors.
Please read this manual thoroughly before installation and keep it for future reference.
2. Safety Information
WARNING: Improper installation or use can lead to equipment damage, electric shock, or serious injury. Always follow these safety guidelines:
- Ensure the power supply is disconnected from the AC power outlet before installation or handling.
- Do not open the power supply unit. High voltages are present inside, even when disconnected.
- Install the power supply in a well-ventilated area, away from heat sources, direct sunlight, and moisture.
- Use only the cables provided with the power supply.
- Ensure all cables are securely connected to prevent short circuits or damage.
- This product is designed for desktop computer use only. Do not use it for other applications.
- Keep out of reach of children.
3. Package Contents
Verify that all items are present in your package:
- Enermax CYBERG II 650W Power Supply Unit
- AC Power Cord
- Mounting Screws
- User Manual (this document)
4. Setup and Installation
Follow these steps to install your Enermax CYBERG II 650W Power Supply:
- Prepare Your System:
Before starting, ensure your computer is completely powered off and unplugged from the wall outlet. Open your computer case to access the power supply mounting area.
- Remove Old Power Supply (if applicable):
If replacing an existing power supply, disconnect all cables from your components (motherboard, GPU, drives, etc.) and unscrew the old PSU from the case. Carefully remove it.
- Install the New Power Supply:
Place the Enermax CYBERG II 650W power supply into the designated PSU bay in your computer case. Ensure the fan is oriented correctly for optimal airflow (typically facing downwards if there's a bottom vent, or inwards if mounted at the top).

Image: Front view of the Enermax CYBERG II 650W Power Supply, showing the fan grille and Enermax logo.
Secure the power supply to the case using the provided mounting screws. Typically, four screws are used at the rear of the case.
- Connect Cables:
The CYBERG II 650W features non-modular flat black cables for easier installation and a cleaner look. Connect the necessary cables to your components:
- 24-pin ATX Motherboard Connector: Connect to your motherboard's main power socket.
- 4+4-pin EPS/CPU Connector: Connect to your motherboard's CPU power socket.
- PCIe 5.1 12V-2x6 Cable (450W): Connect directly to compatible graphics cards. For older GPUs, use the standard 6+2-pin PCIe connectors.
- SATA Power Connectors: Connect to SSDs, HDDs, and optical drives.
- Peripheral (Molex) Connectors: Connect to older peripherals or case fans if needed.

Image: Rear view of the Enermax CYBERG II 650W Power Supply, showing the fixed cables extending from the unit.
Ensure all connections are firm and correctly seated. Avoid excessive bending or straining of cables.
- Cable Management:
Utilize the flat cable design to route cables neatly behind the motherboard tray or in other designated areas of your case to improve airflow and aesthetics.

Image: Enermax CYBERG II 650W Power Supply showcasing its non-modular flat black cables.
- Close Case and Connect AC Power:
Once all components are connected and cables are managed, close your computer case. Connect the provided AC power cord to the power supply's AC inlet and then to a wall outlet or surge protector. Ensure the power switch on the PSU is in the "OFF" position before plugging it in.

Image: Side view of the Enermax CYBERG II 650W Power Supply, highlighting the AC power input and on/off switch.
- Power On:
Flip the power switch on the back of the power supply to the "ON" position. Then, power on your computer using the case's power button.
5. Operating Instructions
The Enermax CYBERG II 650W Power Supply operates automatically once installed and powered on. It provides stable DC voltage to your computer's components.
- Power On/Off: Use the main power switch on the PSU to completely cut power to the unit. For daily use, use your computer's operating system shutdown function and case power button.
- Cooling: The integrated 120mm sleeve bearing fan provides efficient cooling for the power supply. Ensure adequate airflow around the PSU and within the computer case.
- Efficiency: This power supply is 80 Plus Gold certified, meaning it operates with up to 90% efficiency, reducing wasted energy and heat generation.
- Protection Features: The unit includes a 6-way protection circuit (OVP, UVP, OPP, SCP, OCP, OTP) to safeguard your components against various electrical anomalies.
6. Maintenance
Regular maintenance helps ensure the longevity and optimal performance of your power supply:
- Dust Cleaning: Periodically clean the fan grille and interior of your computer case to prevent dust buildup, which can impede airflow and cooling. Use compressed air for this purpose, ensuring the system is powered off and unplugged.
- Cable Inspection: Occasionally check all cable connections to ensure they remain secure and free from damage.
- Environment: Maintain a clean, dry, and well-ventilated environment for your computer.
CAUTION: Do not attempt to open the power supply unit for cleaning or any other reason. This will void the warranty and expose you to dangerous voltages.
7. Troubleshooting
If you encounter issues with your power supply, refer to the following common problems and solutions:
| Problem | Possible Cause | Solution |
|---|---|---|
| Computer does not power on. |
|
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| System powers on but immediately shuts down. |
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| Fan is excessively loud. |
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| Burning smell or smoke. |
| Immediately disconnect AC power and contact Enermax support. Do not attempt to use the unit. |
If the problem persists after attempting these solutions, please contact Enermax customer support.
8. Specifications
Key technical specifications for the Enermax CYBERG II 650W Power Supply:
| Feature | Detail |
|---|---|
| Model Name | CYBERG II |
| Item Model Number | ERV650G-AHG-NAC |
| Brand | Enermax |
| Output Wattage | 650 Watts |
| Form Factor | ATX |
| Connector Type | ATX |
| Efficiency Certification | 80 Plus Gold (up to 90% efficiency) |
| PCIe Support | PCIe 5.1 (with 450W 12V-2x6 cable) |
| Capacitors | 105°C Japanese Capacitors |
| Cooling Method | Air (120mm Sleeve Bearing Fan) |
| Protection Circuit | 6-way (OVP, UVP, OPP, SCP, OCP, OTP) |
| Product Dimensions (L x W x H) | 5.51 x 5.91 x 3.39 inches (140 x 150 x 86 mm) |
| Item Weight | 2.51 pounds (1.14 kg) |
| Compatible Devices | Desktop PC |
| Date First Available | April 25, 2025 |
9. Warranty and Support
Enermax products are manufactured to the highest quality standards. For warranty information and technical support, please refer to the official Enermax website or contact their customer service department.
Enermax Official Website: www.enermax.com
Please have your product model number (ERV650G-AHG-NAC) and purchase date ready when contacting support.
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