PC Power Supply

Micro ATX Power Supply Buying Guide: Comprehensive Analysis of Wattages from 450W to 850W

2025-06-24

In the ever - evolving world of PC components, power supplies play a crucial role in ensuring stable and reliable performance. Micro ATX power supplies, in particular, have gained popularity for their compact size and compatibility with smaller form - factor cases. In this article, we will explore various aspects of Micro ATX power supplies, including different wattage options, their sizes, and how they compare to their ATX counterparts.

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Micro ATX Power Supply Size

One of the main advantages of Micro ATX power supplies is their compact size. They are designed to fit into smaller cases, making them ideal for builds where space is a constraint. Micro ATX power supplies are typically smaller in both length and width compared to standard ATX power supplies. The standard dimensions of a Micro ATX power supply are around 100 - 125mm in width, 63.5 - 86mm in height, and 140 - 150mm in length. This compact size allows for more flexibility in case selection, especially for those who prefer a smaller footprint for their PC. For example, in a small form - factor case like the SilverStone SG13, a Micro ATX power supply can be installed more easily compared to a larger ATX power supply, without sacrificing too much in terms of power output.

Best Micro ATX Power Supplies


GS-450

Micro ATX Power Supply GS-450 | Power Supply

The small form factor power supply for your big ideas. GameMax SFX Series power supplies bring legendary performance and reliability to the SFX small form factor standard
They have the features found in full-size high-performance power supplies, with compliant with 80 PLUS efficiency, superior voltage regulation, along with smart fan controller for better reliability.
Active PFC and Full Range AC Input (100-240V)
Designed for custom-built PCs, mini-servers and HTPCs
Smart auto fan speed controller
The micro SFX design
Safety and EMC certified by CE
High Efficiency up to 85%
Fully protection functions

GS-650G

Micro ATX Power Supply GS-650G | Power Supply

• The GameMax SFX Series Power Supplies offer compact, high-performance solutions designed for small form factor builds, combining efficiency and reliability in one package。
•  Exceptional Performance: Certified 80 PLUS efficiency, precise voltage regulation, and smart fan control ensure dependable operation.
•  Compact and Powerful: The SFX Modular 650W (2024) measures 125mm x 110mm x 65mm, delivering robust power in a small footprint.
•  Optimized Cooling: GameMax hybrid fan control automatically adjusts cooling based on system demands for maximum efficiency.

GS-750G

Micro ATX Power Supply GS-750G | Power Supply

• The GameMax SFX Series Power Supplies offer compact, high-performance solutions designed for small form factor builds, combining efficiency and reliability in one package。
•  Exceptional Performance: Certified 80 PLUS efficiency, precise voltage regulation, and smart fan control ensure dependable operation.
•  Compact and Powerful: The SFX Modular 750W (2024) measures 125mm x 110mm x 65mm, delivering robust power in a small footprint.
•  Optimized Cooling: GameMax hybrid fan control automatically adjusts cooling based on system demands for maximum efficiency.

GS-850G

Micro ATX Power Supply GS-850G | Power Supply

• The GameMax SFX Series Power Supplies offer compact, high-performance solutions designed for small form factor builds, combining efficiency and reliability in one package。
•  Exceptional Performance: Certified 80 PLUS efficiency, precise voltage regulation, and smart fan control ensure dependable operation.
•  Compact and Powerful: The SFX Modular 850W (2024) measures 125mm x 110mm x 65mm, delivering robust power in a small footprint.
•  Optimized Cooling: GameMax hybrid fan control automatically adjusts cooling based on system demands for maximum efficiency.

GS 650G

Micro ATX Power Supply GS 650G | Power Supply

GS 650G 80 Plus Gold Certified SFX Power Supply with Intelligent Cooling, Japanese Capacitors, and Comprehensive Protection
80 Plus Gold Certified Efficiency: Enhances power efficiency and stability, reducing the risk of system crashes.
High-Quality Japanese Capacitors: Ensures long-term reliability and stability with 105°C electrolytic and solid-state capacitors.
Intelligent Fan Control: 9.2cm hydraulic bearing fan with PWM automatic control starts and stops based on power consumption (above 20% and below), optimizing cooling and noise.
Advanced Wireless Output Design: Gold-plated pins and high-density copper posts enable efficient, reliable power output and improved heat dissipation.
Comprehensive Circuit Protection: Provides multi-layered protection (OPP, OVP, UVP, OCP, SCP, OTP) to safeguard your PC and components from damage.

GS 750G

Micro ATX Power Supply GS 750G | Power Supply

GS 750G 80 Plus Gold Certified SFX Power Supply with Intelligent Cooling, Japanese Capacitors, and Comprehensive Protection
80 Plus Gold Certified Efficiency: Enhances power efficiency and stability, reducing the risk of system crashes.
High-Quality Japanese Capacitors: Ensures long-term reliability and stability with 105°C electrolytic and solid-state capacitors.
Intelligent Fan Control: 9.2cm hydraulic bearing fan with PWM automatic control starts and stops based on power consumption (above 20% and below), optimizing cooling and noise.
Advanced Wireless Output Design: Gold-plated pins and high-density copper posts enable efficient, reliable power output and improved heat dissipation.
Comprehensive Circuit Protection: Provides multi-layered protection (OPP, OVP, UVP, OCP, SCP, OTP) to safeguard your PC and components from damage.

GS 850G

Micro ATX Power Supply GS 850G | Power Supply

GS 850G 80 Plus Gold Certified SFX Power Supply with Intelligent Cooling, Japanese Capacitors, and Comprehensive Protection
80 Plus Gold Certified Efficiency: Enhances power efficiency and stability, reducing the risk of system crashes.
High-Quality Japanese Capacitors: Ensures long-term reliability and stability with 105°C electrolytic and solid-state capacitors.
Intelligent Fan Control: 9.2cm hydraulic bearing fan with PWM automatic control starts and stops based on power consumption (above 20% and below), optimizing cooling and noise.
Advanced Wireless Output Design: Gold-plated pins and high-density copper posts enable efficient, reliable power output and improved heat dissipation.
Comprehensive Circuit Protection: Provides multi-layered protection (OPP, OVP, UVP, OCP, SCP, OTP) to safeguard your PC and components from damage.

GS-700

Micro ATX Power Supply GS-700 | Power Supply

The small form factor power supply for your big ideas. GameMax SFX Series power supplies bring legendary performance and reliability to the SFX small form factor standard
They have the features found in full-size high-performance power supplies, with compliance with 80 PLUS efficiency, superior voltage regulation, along with smart fan controller for better reliability.
SFX Modular 700W (2022)The new line of GameMax GS-700 is versatile in its application and powerful with a small footprint
It is a standard SFX unit, measuring at 125 mm (L) x 100 mm (W) x 63.5 mm (H)
The GS-700 is shipped with an SFX to ATX adapter bracket in the box, which allows the power supply to be mounted not only in the SFX form factor chassis, but also a standard ATX chassis should the user prefers to reserve more space for airflow inside the PC case
The GameMax hybrid fan control is always enabled to optimize the cooling according to necessity.

Micro ATX Power Supply vs ATX

Size and Form Factor

The most obvious difference between Micro ATX and ATX power supplies is their size. As mentioned earlier, Micro ATX power supplies are significantly smaller, which is a major advantage for those building in small form - factor cases. ATX power supplies are larger and are designed for standard - sized mid - tower and full - tower cases. If you have a large case with plenty of space, an ATX power supply might be a better option as it can offer more room for cable routing and better ventilation. However, if you're aiming for a compact and portable PC, a Micro ATX power supply is the way to go.

Power Output and Capacity

In general, ATX power supplies tend to offer a wider range of power output options, especially at the higher wattage end. While Micro ATX power supplies are available in wattages up to 1000W, it's more common to find a greater variety of high - wattage ATX power supplies. For example, if you're building a high - end gaming PC with multiple high - end graphics cards and overclocked processors, an ATX power supply might be more suitable as it can more easily handle the high power demands. However, for most mid - range and entry - level builds, Micro ATX power supplies can provide sufficient power.

Cable Management

Micro ATX power supplies, especially those that are fully modular, can be easier to manage in terms of cables in a small case. Since the case is smaller, having only the necessary cables connected reduces clutter. ATX power supplies, on the other hand, come with a larger number of cables, which can be more challenging to route neatly in a small case. However, in a larger ATX case, the extra space can make cable management a bit more forgiving, even with the larger number of cables.

Cost

In some cases, Micro ATX power supplies can be slightly more expensive per watt compared to ATX power supplies. This is because of the additional engineering required to fit all the components into a smaller form factor. However, the price difference is not always significant, and when you consider the cost savings from using a smaller case, the overall cost of a Micro ATX - based build can still be competitive.

In conclusion, Micro ATX power supplies offer a great solution for those looking to build a PC in a smaller form factor without sacrificing too much in terms of power and performance. With a variety of wattage options available, from 450W for basic builds to 1000W for extreme setups, there's a Micro ATX power supply for every need. When choosing between a Micro ATX and an ATX power supply, it's important to consider your case size, power requirements, cable management needs, and budget.