What cooling issues does the SeaSonic FOCUS GX-750 face?

Seasonic FOCUS GX-750 in its cooling system core has built in a 120 mm Hong Hua fan with a hydrodynamic bearing and a hybrid mode. The cooling system works as it is – during low loads, the fan doesn't rotate, but when the temperature gets high, it suddenly starts rotating. It causes a higher noise level, in most cases under the ~60 % system load. Some cases also show coil whine and vibration noise from the fan at peak speeds.

Overall, the Seasonic FOCUS GX-750 cooling system provides stable temperature inside the case. But still, it tends to get louder under high load.

How does the active cooling system with a fan work in the FOCUS GX-750?

The active cooling system in the Seasonic FOCUS GX‑750 works as follows:

• At loads up to ~30%, the fan does not rotate and does not make any noise (Fanless mode).

• At a load of 30-70%, the fan rotates slowly to keep the optimal temperature of the capacitors and power components. And handle it quietly in the background.

• At peak loads above 70%, the fan increases its speed to dissipate heat during peak GPU/CPU power consumption.

Overall, the digital controller regulates the fan speed depending on the temperature of the transformer, power modules, and capacitors. In other words, the Seasonic FOCUS GX‑750 has a smart system that adapts to the cooling PC needs.

What is hybrid fan control in the SeaSonic FOCUS GX-750?

Hybrid Fan Control in FOCUS GX‑750 is a system that automatically regulates fan operation. The user doesn’t even need to turn it on manually. The system determines the temperature in the case and turns off the fan accordingly.

Fanless mode is turned off at low load (<30%), when the fan is not rotating. Quiet mode is activated at medium load, when the fan starts to rotate slowly to keep the optimal temperature. Active mode is turned on when the PC is under a high load. For example, when you are streaming for a long time or playing extremely demanding games. Then the fan starts to speed up for effective heat dissipation.

How is semi-passive cooling different from full-fledged active cooling in power supplies?

Semi-passive cooling differs from full-fledged active cooling in that the fan only turns on when the temperature exceeds a certain level. The advantage of semi-passive cooling in this case is less noise and less fan wear at low loads. Moreover, the system effectively dissipates heat from very hot components under peak loads. Such cases are more common in professional PC assemblies, powerful gaming systems, or streaming stations.

How do high-quality fan bearings ensure reliable cooling?

In Seasonic power supplies, we use only high-quality components to deliver efficient cooling for every PC user and their professional builds. The first is high-quality fan bearings (Fluid Dynamic Bearing). They provide the following:

• Less friction and vibration because the fan rotates smoothly and produces minimal noise.

• An extended lifespan, as the bearings can withstand tens of thousands of hours without degradation.

• Stable airflow. The components stay at an optimal temperature even under prolonged load.

What is the difference between passive cooling, and why is it rare in high-power power supplies?

Passive cooling in PSUs means heat dissipation without the use of fans. Cooling relies solely on radiators and natural convection. It differs from active cooling in that it doesn’t have fans and, accordingly, doesn’t regulate their speed. The system temperature is controlled only by the radiators and the air flow in the case.

High-power PSUs (750 W and above, for example, Seasonic FOCUS GX-1000) generate a lot of heat that cannot be effectively removed by passive means. Without active cooling, components overheat significantly, reducing the stability and PC components longevity. That’s why passive cooling is usually used in low-power, energy-efficient PSUs, 300–400 W range.

What thermal management systems are built into the FOCUS GX-750?

Seasonic FOCUS GX‑750 has the following built-in thermal management systems:

• Hybrid Fan Control. The fan only operates at medium or high loads. When the load is minimal, fanless mode is activated.

• Digital fan speed control. The fan adjusts its speed based on the PSU’s component temperatures.

• A large 135 mm fan with Fluid Dynamic Bearing provides efficient airflow with minimal noise for the PC user.

• High-quality Japanese 105°C capacitors withstand high temperatures without degradation.

• The optimized internal ventilation structure directs airflow through critical PC components for even cooling.

How does the FOCUS GX-750 cooling system differ from other SeaSonic power supplies?

The Seasonic FOCUS GX‑750 differs from other power supplies in this way:

• it has its built-in 135 mm FDB fan,

• hybrid fanless mode,

• precise digital speed control.

Together, they ensure quiet and efficient PC operation even in a compact case.

Conclusion

Seasonic's FOCUS GX-750 is a great choice for gaming PCs, streaming, video editing, and workstation owners who are striving to get stable power and quiet operation. It has innovative, efficient cooling in its core that delivers stable and pleasant performance under any workload.