JUSTOP Black 700W Power Supply Unit ATX PSU With 120MM Quiet Fan vs GameMax 750W Rampage Power Supply
Updated August 2026 — The GameMax 750W Rampage Power Supply offers superior efficiency and cooling features compared to the JUSTOP Black 700W Power Supply Unit, making it the better choice for high-performance builds.
The GameMax 750W Rampage Power Supply offers superior efficiency and cooling features compared to the JUSTOP Black 700W Power Supply Unit, making it the better choice for high-performance builds.
Why JUSTOP Black 700W Power Supply Unit ATX PSU With 120MM Quiet Fan is better
lower price
JUSTOP is £29.95 compared to GameMax at £45.80
adequate features
sufficient for basic systems
compact design
traditional ATX design fits most cases
Why GameMax 750W Rampage Power Supply is better
higher efficiency
GameMax is 80 Plus Bronze certified
better cooling
larger 14CM fan for improved airflow
semi-modular design
simplifies cable management and installation
Overall score
Specifications
| Spec | JUSTOP Black 700W Power Supply Unit ATX PSU With 120MM Quiet Fan | GameMax 750W Rampage Power Supply |
|---|---|---|
| Power Output | 700W | 750W |
| Efficiency | 70% | up to 88% |
| Cooling Fan | 12CM | 14CM |
| Protection Features | OVP, OPP, SCP | OVP, OPP, SCP, Japanese Capacitors |
| Modularity | Non-Modular | Semi-Modular |
Dimension comparison
Overview of the Power Supplies
The JUSTOP Black 700W Power Supply Unit and the GameMax 750W Rampage Power Supply cater to different needs in the gaming and computer-building communities. Both products offer reliable power solutions, but they differ in design, efficiency, and features. The JUSTOP is priced at £29.95, while the GameMax comes at a higher price point of £45.80, reflecting their respective capabilities and target audiences.
Design and Build Quality
The design of a power supply can significantly impact both aesthetics and functionality in a PC build. The JUSTOP features a traditional ATX design with a 12CM quiet cooling fan, ensuring good airflow while maintaining a low noise level. In contrast, the GameMax boasts a semi-modular cable management system, allowing for a cleaner and more efficient build. This feature not only simplifies the installation process but also enhances airflow within the case. While both units are built to provide quality power, the semi-modular design of the GameMax may appeal more to users who prioritise aesthetics and ease of installation.
Efficiency Ratings
Efficiency is a crucial factor for power supplies, impacting both performance and energy consumption. The JUSTOP has a stated efficiency of over 70%, which is adequate for basic and mid-range systems. On the other hand, the GameMax is 80 Plus Bronze certified, achieving efficiency levels of up to 88% at a 50% load. This certification indicates that the GameMax is designed to waste less power and generate less heat, making it a better choice for high-performance builds. The enhanced efficiency of the GameMax can lead to lower electricity bills and a more eco-friendly setup.
Cooling Performance
Cooling efficiency plays a vital role in the longevity and stability of a power supply. The JUSTOP comes equipped with a 12CM fan that operates at a noise level of 40dBA, providing adequate cooling for most setups. Meanwhile, the GameMax utilises a larger 14CM cooling fan, which not only contributes to quieter operation but also enhances its cooling capabilities. The larger fan can move more air at lower RPMs, contributing to a cooler overall system. Users looking for a power supply that prioritises thermal management may find the GameMax to be the superior option.
Compatibility and Connectors
Both power supplies offer a range of connectors designed to support different components. The JUSTOP provides a comprehensive set of connectors, including a 24 pin, 8 pin 12V, 1 PCI-E 8-Pin, and multiple SATA and Molex connectors. This makes it compatible with a variety of motherboards and components. The GameMax similarly offers a robust selection but with the added advantage of its semi-modular design, allowing users to connect only the cables they need. This feature can simplify cable management and improve airflow within the case, making the GameMax a better choice for users with specific connection requirements.
Protection Features
Safety is paramount in power supply units, and both the JUSTOP and GameMax incorporate several protection mechanisms. The JUSTOP includes over voltage protection, over power protection, short circuit protection, and thermal overload cut-off protection, ensuring reliable operation under various conditions. The GameMax also offers similar protections but emphasises the use of high-quality Japanese TK main capacitors, which enhance reliability and lifespan. While both units provide essential safety features, the quality of components in the GameMax may give it an edge in long-term durability.
Price Comparison
When it comes to pricing, the JUSTOP Black 700W is significantly more affordable at £29.95, making it an attractive option for budget-conscious builders. In contrast, the GameMax 750W Rampage is priced at £45.80, reflecting its enhanced features and performance capabilities. While the JUSTOP offers great value for entry-level systems, the additional investment in the GameMax may be justified for users seeking higher efficiency and better cooling solutions. Ultimately, the choice may hinge on the builder's budget and performance requirements.
Which should you buy?
Choosing between the JUSTOP Black 700W Power Supply Unit and the GameMax 750W Rampage Power Supply depends largely on your specific needs and budget. If you are an entry-level builder looking for a reliable and cost-effective option, the JUSTOP is a solid choice with its adequate power and essential features. However, if you are building a high-performance gaming rig and desire superior efficiency, enhanced cooling, and a more aesthetically pleasing setup, the GameMax is worth the extra investment. Consider your priorities in terms of performance, design, and budget to make the best decision for your build.
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