1. Introduction
This manual provides comprehensive instructions for the installation, operation, and maintenance of your Sapphire NITRO+ S240-A Liquid CPU Cooler. Please read this manual thoroughly before installation to ensure proper setup and optimal performance. This All-in-One (AIO) liquid cooler is designed to provide efficient cooling for your CPU, featuring a 240mm radiator, two high-performance fans, and an Asetek 7th generation pump.
2. Safety Information
- Always disconnect power from your computer before installing or performing maintenance on any components.
- Handle components with care to avoid damage. Static electricity can harm electronic parts; consider using an anti-static wrist strap.
- Ensure all cables are connected securely and correctly to prevent electrical shorts or malfunctions.
- Do not open the liquid cooler's pump or radiator. It contains a sealed liquid cooling system.
- Keep out of reach of children.
3. Package Contents
Verify that all items are present in your package:
- Sapphire NITRO+ S240-A AIO Liquid Cooler (Radiator, Pump, Tubing)
- 2x 120mm Cooling Fans
- Mounting Hardware Kit (for Intel and AMD sockets, including LGA1700)
- Fan Screws and Radiator Screws
- Thermal Paste (pre-applied or in a tube)
- RGB/Fan Controller (if applicable)
- User Manual (this document)

Image: The retail packaging for the Sapphire NITRO+ S240-A liquid CPU cooler, showing the product name and design.
4. Setup and Installation
Follow these general steps for installing your liquid CPU cooler. Specific steps may vary slightly depending on your motherboard and PC case. Refer to your motherboard and case manuals for detailed instructions.
4.1 Prepare the Motherboard
- Install the appropriate backplate for your CPU socket (e.g., LGA1700, AM4) onto the rear of the motherboard.
- Attach the standoffs to the front of the motherboard, securing them through the backplate.
4.2 Install the Fans on the Radiator
Attach the two 120mm fans to the radiator using the provided long screws. Ensure the fan airflow direction is correct for your case's cooling configuration (typically pushing air through the radiator and out of the case, or pulling air in).

Image: Top view of the radiator assembly with two fans installed, showcasing the RGB lighting.
4.3 Mount the Radiator
Install the radiator assembly into your PC case. Common mounting locations include the top or front of the case. Secure the radiator using the shorter screws provided.
4.4 Install the Pump/Cold Plate
- Ensure the CPU surface is clean. If thermal paste is not pre-applied, apply a small amount (pea-sized dot) to the center of the CPU.
- Carefully place the pump/cold plate assembly onto the CPU, aligning it with the standoffs.
- Secure the pump to the standoffs using the appropriate thumb screws or nuts, tightening them in a diagonal pattern until snug. Do not overtighten.

Image: A side view of the Sapphire NITRO+ S240-A, showing the pump block connected to the radiator via tubing, with white fans installed.
4.5 Connect Cables
- Connect the pump power cable to the CPU_FAN or AIO_PUMP header on your motherboard.
- Connect the fan cables to the CPU_FAN or SYS_FAN headers on your motherboard, or to an included fan controller.
- If your cooler has RGB lighting, connect the RGB cables to the appropriate motherboard RGB header (e.g., 3-pin ARGB) or to an RGB controller.

Image: A detailed view of the pump head, highlighting its unique spider design and customizable Addressable RGB LED lighting.
5. Operating Instructions
5.1 Initial Power-On
After installation, power on your computer. The fans and pump should start operating. Monitor your CPU temperatures using system monitoring software to ensure proper cooling.
5.2 RGB Lighting Control
The Sapphire NITRO+ S240-A features Addressable RGB LED lighting on the pump cap and fans. This can typically be controlled via your motherboard's RGB software (e.g., ASUS Aura Sync, MSI Mystic Light, Gigabyte RGB Fusion) or a dedicated Sapphire software if available. Refer to your motherboard's manual for RGB software usage.
6. Maintenance
Regular maintenance helps ensure the longevity and optimal performance of your liquid cooler.
- Dust Cleaning: Periodically clean dust from the radiator fins and fan blades using compressed air or a soft brush. Ensure the fans are not spinning during cleaning.
- Cable Management: Ensure all cables are neatly routed and not interfering with fan operation or airflow.
- Leak Inspection: While the system is sealed, occasionally inspect the tubing and connections for any signs of leakage. If a leak is detected, immediately power off your system and contact support.
7. Troubleshooting
If you encounter issues with your Sapphire NITRO+ S240-A, refer to the following common troubleshooting steps:
- No Power/Fans Not Spinning: Check all power connections to the pump and fans. Ensure they are securely plugged into the correct headers on the motherboard or controller.
- High CPU Temperatures:
- Verify the pump is running (you might feel a slight vibration or hear a faint hum).
- Ensure the cold plate is making proper contact with the CPU. Re-seat the cooler if necessary, applying new thermal paste.
- Check fan orientation and ensure they are pushing/pulling air effectively through the radiator.
- Clean any dust buildup on the radiator fins.
- Excessive Noise:
- Identify if the noise is coming from the fans or the pump.
- For fan noise, check for obstructions or loose screws. Adjust fan speed settings in BIOS or software.
- Pump noise can sometimes occur during initial startup as air bubbles clear. If persistent, ensure the pump is mounted correctly and is not the highest point in the loop (to prevent air from collecting in the pump).
- RGB Lighting Not Working: Check RGB cable connections to the motherboard or controller. Ensure RGB software is installed and configured correctly.
8. Specifications
| Feature | Specification |
|---|---|
| Brand | SAPPHIRE |
| Model Number | 4N005-01-20G |
| Cooling Method | Liquid (Thermal) |
| Radiator Size | 240mm |
| Fan Size | 120mm (x2) |
| Noise Level | 24 Decibels |
| Voltage | 12 Volts |
| Pump Technology | Asetek 7th Generation |
| Tubing Material | Nylon Mesh Sleeved EPDM |
| RGB Lighting | Addressable RGB LED |
9. Warranty and Support
9.1 Warranty Information
This product comes with a 2-year warranty from the date of purchase. To claim warranty service, proof of purchase (receipt or invoice) is required. The warranty is valid for use within Japan only. Please retain your purchase documentation.
9.2 Technical Support
For technical assistance, troubleshooting, or warranty inquiries, please contact your retailer or the official Sapphire support channel. Visit the official Sapphire website for the most up-to-date support contact information and resources.
Official Website: www.sapphiretech.com



