Your PC relies on a consistent stream of power to stay on—but sometimes, your mains supply may not be so reliable. So if you live in a neighborhood prone to outages, you might be wondering: can a power outage damage a PC, and what can you do to protect yourself from its effects?

Let's explore the risks of a power outage, how to avoid them, and the damage and power outage or surge can do to your computer.

What Causes Blackouts, Brownouts, and Power Surges?

A lightning storm over a city

The electricity flowing through your home is not constant. Electrical currents can ebb and flow, dipping above and below what's ideal. Both too much and too little power can cause problems.

When power completely shuts off, it's known as a blackout. These tend to occur due to issues beyond your control (e.g., power station disruptions, damaged electrical lines, etc.), but sometimes they can be self-inflicted (e.g., by shorting or overloading circuits).

A similar issue called a brownout is when your electrical voltage experiences a temporary drop without fully blacking out.

If you've ever seen your lights dim for unknown reasons, it was probably due to a brownout. These can be intentional to reduce electrical loads and prevent blackouts, though they can also be unintentional. There's also load-shedding, also known as rolling blackouts, which are intentional blackouts designed to protect large electrical grids from becoming overwhelmed, leading to a full blackout.

On the other side of the spectrum, there's the power surge. This is when an appliance receives more electricity than intended for at least three nanoseconds.

Power surges happen due to several factors, including short circuits and electrical line malfunctions. However, if the increased voltage only lasts one or two nanoseconds, it's likely caused by lightning.

Can a Power Cut Damage Your PC?

Computer hardware

So, can a sudden drop in power cause problems for your PC? As it turns out, yes, both for your data and hardware.

How a Power Cut Can Damage Your Computer

Sudden shutdown after a blackout is the primary danger to a computer's health. Operating systems are complex and must go through a "shutdown sequence" to ensure all running processes have correctly terminated before powering off.

A sudden loss of electricity will interrupt this sequence and may leave processes "half-finished," which can corrupt files and threads, damaging the operating system.

System files are the largest concern. A sudden cut will corrupt the file if the operating system is busy editing an important file when the power outage hits (such as during a system update). Then, when you try to reboot the computer, the operating system crashes over this corrupted file and fails to boot.

If you're lucky enough that your system files are unscathed, you may still lose vital work. If you don't get into the habit of constantly saving your work, a power cut could set you back to square one. Power cutting out mid-save may corrupt your work.

Furthermore, frequent power outages can reduce the hard drive's physical lifespan. This is because the read-and-write head, which hovers over the spinning platters during operation, snaps back into its original position upon power loss.

This sudden movement can cause tiny imperfections that accumulate over time, increasing the likelihood of a "head crash." This is when the head touches and scrapes the platter surfaces, effectively destroying the hard drive.

Solid-state drives can also suffer catastrophic damage from sudden power cuts. Issues can range anywhere from data corruption to total malfunction. As per Kingston, many solid-state drives have power-loss protection (PLP), but "Early generation SSDs were not as resilient to sudden power loss as today's models." So, if you have a much older solid-state drive and you live in an area with known power grid issues or that experiences extremes in weather, upgrading your SSD could be worthwhile.

How Post-Blackout Power Surges Can Damage Your Computer

What's worse, a power outage may not be the end of your problems. A surge often follows up an outage once the electricity comes back online.

A power surge will overload and fry the electronics within your PC. While an outage doesn't do a great deal of damage to a power supply or motherboard, the subsequent surge will. This will result in a computer that won't turn on after a power outage occurs.

As such, if you want to stay safe from a power outage, it's also worth investing in power surge protection. There's nothing worse than skillfully negating a blackout, only for everything to fry due to the surge afterward!

How to Protect Against Power Outages

While power outages won't tear through a computer as a power surge will, they can still do damage. As such, if you want to take care of your data's health, it's a good idea to invest in some anti-outage precautions.

Using an Uninterruptable Power Supply (UPS) to Prevent Power Outage Damage

For protection against power outages, you need an uninterruptible power supply. A UPS contains a backup battery that will continue to provide power to your computer even when your power goes out.

UPS devices can also come equipped with surge-protected outlets, making them a useful two-for-one purchase. A UPS will be a strong investment if you live in a building or location that frequently experiences outages, surges, or both.

It's important to note that a UPS unit only powers your electronics for a few minutes. This means it's not a great solution if you want to continue working through an outage.

However, those few minutes give you plenty of time to shut down your computer manually to prevent damage. In addition, UPSs can sound an alarm to alert you of an outage or even tell your PC to shut down immediately.

Using a Laptop to Work Through Outages

If you instead want to continue working through a power cut, why not use a laptop? Laptops entirely avoid power outages; it switches to the battery when the electricity cuts out.

As such, if you're in an area that suffers from power cuts frequently, it may be worth changing to a laptop. While laptops aren't as powerful as a full PC, they're far more usable when the power drops out than a computer.

Of course, it doesn't feel good to buy a laptop just because your power situation isn't ideal. Fortunately, grabbing a work laptop doesn't have to break the bank. Be sure to check out the cheapest high-quality laptops for an affordable way to continue working through outages.

Get a Good Surge Protector for Post-Blackout Power Surges

Whichever means you choose to protect your data from sudden shutdowns, you also should enhance it with surge protection.

While this doesn't protect your hardware from the actual blackout, it does shield it from any power surges that happen post-blackout. As such, a surge protector protects you from every danger that can occur during a blackout while also stopping power surges.

Buying a surge protector can be a little confusing, as they come with specifications that detail how good they are at their job. If terms such as "UL Rating" and "Clamping Voltage" make your head spin, consult our guide on if surge protectors are necessary.

Protect Your Computer From Power Surges and Outages

Power outages can damage system files and data, and the subsequent power spikes can destroy hardware. As such, if you live in a neighborhood with unstable power, you should take the time to protect against both and save some headaches.

Unfortunately, power cuts are one of the many ways you can damage your hardware. So if you're purchasing a new PC or building one from scratch, it's a good idea to learn all the ins and outs of maintaining it to keep it running as long as possible.