CORSAIR CX650 80 PLUS Bronze Non Modular Low-Noise ATX 650 Watt Power Supply - U vs CORSAIR RM750e

Pricing

When comparing the pricing of the CORSAIR CX650 and the CORSAIR RM750e, there is a notable difference. The CX650 is priced at £44.99, while the RM750e is significantly higher at £81.99. This £37 price gap reflects the differences in features and capabilities between the two power supplies. The lower price of the CX650 may appeal to budget-conscious consumers, but it is essential to consider what additional features the RM750e offers that justify its higher cost.

Efficiency

The CORSAIR CX650 boasts an 80 PLUS Bronze certification, achieving up to 88% operational efficiency. This means that it generates less heat and lowers energy costs compared to many non-certified power supplies. In contrast, the RM750e does not list a specific efficiency rating in the provided details, but it is designed to be compliant with the Intel ATX 3.1 power standard, which generally indicates a higher efficiency and better performance under load. Consumers prioritising energy efficiency may lean towards the CX650 for its clear certification.

Modular Design

A critical difference between the two power supplies is their cabling design. The CORSAIR CX650 is a non-modular unit, meaning all cables are permanently attached, which can lead to a more cluttered build and potentially obstruct airflow. In contrast, the CORSAIR RM750e features a fully modular design, allowing users to connect only the cables needed for their specific setup. This modularity not only simplifies installations but also enhances cable management, making the RM750e a better choice for those who value aesthetics and airflow.

Noise Levels

When it comes to noise, the CORSAIR CX650 is equipped with a thermally controlled 120mm cooling fan that operates quietly at lower loads, only ramping up when under heavy stress. This design prioritises a low-noise operation, making it suitable for quieter builds. The RM750e, on the other hand, also features a 120mm rifle bearing fan that is designed to keep noise levels down, even at full load, thanks to its specially calculated fan curve. Both power supplies aim for quiet operation, but the RM750e may offer a slight edge in performance under stress.

Performance Under Load

Performance under load is an essential factor to consider in a power supply. The CORSAIR CX650 guarantees its full rated wattage of continuous power at 650 watts, making it reliable for various gaming and productivity setups. In comparison, while the RM750e provides 750 watts, it is also compliant with the latest ATX power standard, supporting PCIe 5.1. This means it can handle transient power excursions from high-demand components like GPUs more effectively, making it a superior choice for high-performance systems.

Thermal Management

Thermal management is crucial for the longevity and reliability of any power supply. The CORSAIR CX650’s low-noise cooling fan is designed to adjust its speed based on the operational load, which helps maintain optimal temperatures while reducing noise. The RM750e takes this further with its rifle bearing fan, which not only keeps the unit quiet but also enhances cooling efficiency during heavy loads. This efficient thermal management makes the RM750e more suitable for high-performance builds where heat can be a concern.

Capacitor Quality

The quality of capacitors used in a power supply can significantly influence its performance and reliability. The CORSAIR CX650 does not specify the quality of its capacitors, while the RM750e uses 105°C-rated capacitors. These higher-rated capacitors are designed to deliver steady and reliable power, ensuring dependable electrical performance over time. For users looking for long-term reliability, the RM750e’s superior capacitor quality is a notable advantage.

Which should you buy?

Ultimately, the decision between the CORSAIR CX650 and the CORSAIR RM750e hinges on your specific needs and budget. If you are looking for an economical and efficient option with satisfactory features, the CX650 at £44.99 is a solid choice. However, if you need a power supply that offers better modularity, higher wattage, and enhanced thermal management, the RM750e at £81.99 justifies its price with advanced features and superior performance. For high-performance builds or users who prioritise efficiency and quiet operation, the RM750e would be the recommended choice.