Can a Bad Power Supply Damage a Hard Drive? (Answered)

The function of the PC depends on the seamless working of the PSU (Power supply unit). Because it provides the power to each hardware component and enables it to function effectively. But what if the PSU is bad? Can it fry your hard drive?

In this article, we shall discuss whether a bad power supply has the potential to damage a hard disk drive (HDD). Also, we shall explore the preventive measures and tips to find out a bad PSU.

Can a Bad Power Supply Damage a Hard Drive

Can a Bad Power Supply Damage a Hard Drive?

A bad power supply unit can damage a hard drive and pretty much any hardware in the PC. Since the PSU delivers the necessary power for the components to work, a fault in its system will result in a power failure or power surge. This can cause the components like HDD to get damaged and may also damage other hardware like the motherboard.

As the name suggests, PSU supplies the required amount of power to all the hardware components. To be precise, it delivers the power needed for the PC components to work and the hardware draws the sufficient power they needed for their function.

When there is a fault in the PSU, the hardware components may have an insufficient supply or excess supply. Both scenarios are dangerous for the working of components. Especially mechanical drives like the HDD can easily get affected due to power fluctuations.

Let us understand what happens during both cases in an HDD and find ways to prevent them from happening.

Insufficient Power from PSU

When PSU is faulty, there are chances for it to provide less than the specified wattage. The HDD has a certain rated wattage within which it can function.

Due to the low power supply from the PSU, the HDD will not be able to actuate and work properly. When there is fluctuation within the low wattage, this will damage the mechanical parts and result in the failure of the HDD.

The HDD has both electronic and mechanical parts. The mechanical parts are governed by the feedback from the electronic system. When there is very low power, the electronic circuit may not signal the mechanical drives to function.

During a fluctuation, the circuits may try to signal the drives constantly which results in the seizing of the motors. So, the HDD will not be able to read or write.

Power Surge from PSU

Although the PSUs are equipped with over voltage protection, they cannot hold beyond a certain voltage limit. Even if you use a surge protector, you should periodically check its integrity and change it.

When these systems fail, there are chances of a power surge that will pass through the PSU and affect hardware like the HDD.

As we mentioned earlier, HDDs have circuits that govern the working of their mechanical drives. Due to a sudden surge in power, the circuit will not be able to resist too much voltage, and this fries up the HDD’s motor.

The whole mechanical setup may get jammed up or the heads may get completely stuck. After this, you cannot use the HDD any longer and have to go for a replacement.

Read: Do PC power supplies have short circuit protection?

In particular, the power surge condition is quite dangerous since you have to take more precautions with your PSU.

Therefore, improper function of any PSU will lead to damage to HDD very easily. Even without such severe spikes or low power, the components will get damaged eventually. Having a poor PSU in your PC is always dangerous and it may lead to repairing or replacing the entire PC itself.

Precaution tips that do not damage the hard drive

If you want your HDD to be safe and avoid any damage from PSU, you can take the following precautions and avoid them.

Earth your Electrical supply

Although many houses are installed with proper earthing, there can be some exceptions. If you don’t have proper earthing, it will affect the PSU in your PC.

The excess current starts lingering around the metal parts of the PSU as well as the internal hardware of the HDD. This eventually builds up and causes electrical damage. They will also fail suddenly, and you have to replace the components.

Therefore, to prevent any kind of electrical damage to your HDD, try to provide earthing to your electrical supply.

Use a Surge Protector

Even if you have all the OVP and OCP circuits in your PSU, they cannot handle heavy power surges from lightning strikes. It can cause severe damage to your entire PC including the HDD.

Therefore, you can add a common surge protector to the mains and a local protector at the socket in which you are going to plug in your PC’s PSU.

This will protect your PC from violent power surges and prevents damage to hardware like the HDD.

Also, remember to replace the protector after an event of surge or lightning strikes since the protectors can also get damaged severely.

Read: Best way to monitor CPU temperature

How do I know the power supply is bad?

If you can find out the improper functioning of the PSU prior to an event, you can prevent severe damages, repairs, and replacements. Here are some signs that can show the poor working of the PSU:

  • Unexpected Shutdowns – When the PC is working fine, suddenly it will shut down for no reason. Even if you have power and all the things are working properly, the PC may shut down without any reason. This is a major sign that your PSU is failing.
  • Poor Functions of PC Hardware – If your PSU is not working fine, the PC may freeze or hang up often. Especially if the PSU is affecting the HDD, you can find the file access to be slower or get jammed up frequently.
  • Not booting up – Your PC may not boot up and may take a lot of time even if manages to boot up. This is also a classic sign of PSU issues.

If you can take note of these issues and start to rectify them as soon as possible, you can avoid damage to the hardware.

Read: Does the Power Supply Affect Performance?


PSU plays a crucial role in the functioning of any PC. Without its proper function, it will cause serious damage to the hardware. HDD is a delicate component of a PC since it has mechanical parts associated with it. Therefore, it is important to keep a check on the proper working of the PSU to avoid failures.

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