CORSAIR RM850x Fully Modular Low-Noise ATX Power Supply vs Be Quiet! Pure Power 13M ATX 3.1-850w - 80 Plus Gold
Updated August 2026 — The CORSAIR RM850x offers superior features and efficiency, making it the better choice despite its higher price.
The CORSAIR RM850x offers superior features and efficiency, making it the better choice despite its higher price.
Why CORSAIR RM850x Fully Modular Low-Noise ATX Power Supply is better
Modularity
Fully modular design for easier installation.
Efficiency
Higher efficiency rating of up to 91%.
Compatibility
Native 12V-2x6 connector for modern GPUs.
Why Be Quiet! Pure Power 13M ATX 3.1-850w - 80 Plus Gold is better
Price
More budget-friendly at £108.79.
Brand
Strong reputation for silent operation.
Wattage
Same wattage capacity of 850W.
Overall score
Specifications
| Spec | CORSAIR RM850x Fully Modular Low-Noise ATX Power Supply | Be Quiet! Pure Power 13M ATX 3.1-850w - 80 Plus Gold |
|---|---|---|
| Brand | Corsair | be quiet! |
| Certification | 80 Plus Gold | 80 Plus Gold |
| Cabling | Fully Modular | Non-specified |
| ATX Compliance | 3.1 | 3.1 |
| Native Connector | 12V-2x6 | Not specified |
Dimension comparison
Overview of the Products
When comparing the CORSAIR RM850x Fully Modular Low-Noise ATX Power Supply and the Be Quiet! Pure Power 13M ATX 3.1-850w - 80 Plus Gold, the primary takeaway is their price and performance in the realm of power supplies. The CORSAIR RM850x is priced at £124.40, while the Be Quiet! Pure Power 13M is slightly more affordable at £108.79. Both power supplies boast an 850W capacity with an 80 Plus Gold certification, ensuring high efficiency, but they cater to slightly different user needs with their unique features.
Brand Reputation and Reliability
Brand reliability is a crucial factor when choosing a power supply, and both Corsair and Be Quiet! have established strong reputations. Corsair is renowned for its high-performance components, often favoured by gamers and PC builders for their durability and efficiency. The RM850x showcases this with its Cybenetics Gold-Certified efficiency rating of up to 91%, which translates to lower power consumption and cooler operating temperatures. On the other hand, Be Quiet! is synonymous with silent operation and quality; however, specific details about the Pure Power 13M's features are less defined, simply branded as 'Bequiet'. This vagueness might concern potential customers looking for specific performance metrics.
Modular Design and Ease of Installation
The modular design of a power supply significantly affects the ease of installation and cable management. The CORSAIR RM850x offers a fully modular cabling system, allowing users to connect only the cables necessary for their builds. This feature not only simplifies the setup but also enhances airflow within the case, which is vital for maintaining optimal temperatures. In contrast, while the Be Quiet! Pure Power 13M is compliant with the ATX 3.1 standard, it lacks specific details about its modularity. Without this information, it's difficult to ascertain how it compares in terms of installation convenience.
Efficiency and Power Rating
Efficiency is a standout feature of both power supplies, given their 80 Plus Gold certifications. The CORSAIR RM850x claims an impressive efficiency rating of up to 91%. This high efficiency means that less power is wasted as heat, contributing to a cooler system overall. The Be Quiet! Pure Power 13M also benefits from the same 80 Plus Gold certification, suggesting a similar level of efficiency, but without explicit efficiency figures provided, it’s challenging to directly compare their performance in this area.
Compatibility with Modern Hardware
Compatibility with the latest hardware is essential for future-proofing any power supply. The CORSAIR RM850x is ATX 3.1 compliant, meaning it supports PCIe 5.1 connections, crucial for the latest graphics cards. Additionally, it includes a native 12V-2x6 connector, ensuring seamless compatibility without needing adapters. In contrast, the Be Quiet! Pure Power 13M does not specify such compatibility features, which could be a vital consideration for users planning to utilise the latest technology in their builds.
Noise Levels
Noise levels are a key consideration, especially for users who prefer a quiet computing environment. The CORSAIR RM850x is specifically marketed as a low-noise power supply, enhancing its appeal for silent builds. While the Be Quiet! Pure Power 13M falls under the Be Quiet! branding, which implies quieter operation, there are no specific noise metrics provided. This lack of information makes it difficult to determine how it stacks up against the RM850x regarding noise performance.
Price Comparison
In terms of pricing, the CORSAIR RM850x comes in at £124.40, while the Be Quiet! Pure Power 13M is more budget-friendly at £108.79. This price difference of £15.61 may influence buyers looking for value, especially considering both units offer similar wattage and efficiency ratings. However, the added features of the RM850x, such as its modularity and advanced compatibility, may justify the higher price for users seeking a more robust power solution.
Which should you buy?
Choosing between the CORSAIR RM850x and the Be Quiet! Pure Power 13M ultimately hinges on your specific needs and preferences. If you value modularity, high efficiency, and compatibility with the latest hardware, the CORSAIR RM850x stands out as the superior choice despite its higher price of £124.40. However, if budget is your primary concern and you are more lenient about specific features, the Be Quiet! Pure Power 13M at £108.79 offers solid performance without breaking the bank. Each power supply has its strengths, so consider your requirements carefully before making a decision.
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