Your BIOS is vital to your computer’s operation but, unfortunately, isn’t impervious to corruption.
processing chip being removed from motherboard
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Key Takeaways
Yes, your BIOS can get corrupted like any other component. Look out for signs like failed OS boot, random shutdowns, and BSOD.
CMOS problems can lead to BIOS corruption. Viruses, power surges, and failed updates are common causes.
BIOS corruption affects the POST process, blocking OS boot and preventing system diagnostics. Be aware of signs and causes.
Your computer’s BIOS plays a crucial role in its operation. Without BIOS installed and active, your PC’s operating system cannot communicate with connected hardware, making it impossible to run normally. With the BIOS being such an important element, it’s worth knowing if or how it can get corrupted and what the signs of BIOS corruption are.
Can Your BIOS Be Corrupted?
close up shot of computer motherboard
In short, yes. Your BIOS can become corrupted like any other crucial component of your PC.
If your BIOS has been corrupted, you won’t get the odd, unusual symptom here and there. A failed BIOS has a huge impact on your computer, so you’ll notice an issue immediately. There are some possible signs of BIOS corruption to look out for, including:
Failed OS boot
Random shutdowns
Blue Screen of Death (BSOD)
POST error messages
The computer turns on and then off
The problems caused by a corrupt BIOS affect your computer’s POST. The Power On Self Test (POST) is a startup process your PC performs to assess key system diagnostics. Just before the operating system is booted, the POST takes place. Without this process, your PC’s components can’t be checked for issues, and the OS boot will be blocked.
What Causes BIOS Corruption?
The BIOS firmware settings are stored in the CMOS, a small chip found on the motherboard of a PC. Problems with the CMOS can lead to problems with the BIOS, so it’s important to note that these two elements are directly linked. The causes listed below often affect the CMOS first, which, in turn, causes BIOS corruption.
1. Viruses and Malware
Viruses and malware don’t just affect the software programs on your computer; they can also affect hardware. Certain viruses and malware programs can hide within BIOS firmware and are specifically designed to cause boot issues after infection (known as a persistent bootkit or rookit infection).
Take the Chernobyl Windows virus, for example. This was the first virus to specifically affect hardware components, emerging in the late 90s. By overwriting crucial functions and corrupting the BIOS, the Chernobyl virus caused critical issues in infected PCs.
BIOS-based viruses are often designed to affect a PC’s bootloader, the software that loads your operating system upon startup. BIOS-based malware and bootkits are designed to be harder to detect, such as MoonBounce, but it’s important to note that malware and viruses made to infect the BIOS are pretty rare.
2. Power Surges
image of electrict current running externally between two conductors
Power surges can cause a slew of PC issues, including BIOS corruption. Power surges may last less than a second, but they can do a lot of damage to a computer. If the power supply to your PC is disrupted in some way (say, through a power outage or cable issue), a power surge can occur, wherein an excess amount of electricity passes through your device. This can damage important components, including the BIOS.
However, it’s important to note that BIOS corruption via a power surge will likely only occur if the surge takes place during a BIOS update.
3. Failed BIOS Update
Because your BIOS is firmware, not hardware, it can be updated for improved performance. Conducting a BIOS update can remove bugs, improve security and stability, and boost hardware compatibility.
If your BIOS is going through an update, but the process fails, it can lead to firmware corruption. A failed update can most commonly be caused by a power failure or surge (as mentioned above), but other factors, including human error, can also play a role.
Your BIOS Isn’t Impervious to Corruption
Your PC’s BIOS is vital for normal operation but is, unfortunately, vulnerable to failure and corruption. It’s important to be aware of how the BIOS can be corrupted, as well as the most common signs that indicate corruption has taken place.