Final answer:
To address a slowly turning power supply fan, first try cleaning it to remove any dust or debris. If that doesn't help, check the power supply connections. Should the issue persist, replacing the fan is the likely solution as fan speed is typically not user-adjustable.
Step-by-step explanation:
If the power supply fan is turning too slowly, the first course of action would be to clean the power supply fan. Dust and debris can accumulate on the fans and obstruct smooth rotation, leading to reduced speed and efficiency. Cleaning the fan will often resolve this issue. If cleaning does not help, you could check the power supply connections to ensure that there is no power issue causing the fan to slow down. If the fan is still not performing adequately after these steps, you may need to replace the fan, especially if the fan is old or has sustained physical damage. The option to increase the power supply fan speed is generally not available since the fan speed is regulated by the power supply unit and not user adjustable.