Most computer problems stem from hardware or software errors. However, it's not always easy to determine why your computer isn't working, and finding the cause of the problem is often frustrating.
Why is it not always clear whether the cause is software or hardware?

Even experienced technicians can be fooled when determining the cause of a problem. For example, the author of the article has a high-spec Dell XPS laptop that frequently crashes with BSOD errors or random crashes.
If the problem is caused by the device overheating, then this is usually a hardware issue. The author has conducted all the usual tests and everything seems fine; both software and hardware work normally. The author even did a clean install of Windows and updated the operating system to Windows 11, but the problem still persisted.
The laptop is also disassembled for inspection to ensure all fans are clean, the heatsink is installed properly, and to see if there are obvious signs of hardware failure. Again, the exact cause cannot be determined.
Finally, a tool called Power Settings Explorer solved the mystery. Dell provides this laptop with a setting called Processor Boost Mode, set to Aggressive. Changing this setting from Aggressive to Enabled resolved the issue.
Symptoms of software and hardware problems

In most cases, determining the root of a computer problem is not too difficult. Let's start by looking at common symptoms that often get you on the right track.
Symptoms of hardware problems
There are obvious symptoms like the computer not turning on that are clearly related to the hardware. However, other symptoms to look out for include:
- Frequently crashes or freezes: This could indicate faulty hardware, such as RAM or GPU, especially during high-demand tasks like gaming or video editing.
- Abnormal noise: Clicking, grinding, or humming noises often signal a hard drive (HDD, not SSD) or fan problem.
- Overheating or sudden shutdown: Indicates a problem with the cooling system or component failure.
- Peripheral error: Unresponsive ports, keyboards, or other connected devices may suggest a motherboard or connector problem.
- Display phenomenon or problem: Flickering pixels, screen, or distorted colors indicate a GPU or display problem.
Hardware failures are often more persistent and can be quite random and inconsistent. Additionally, they can get worse over time if not treated quickly.
Symptoms of software problems
Software problems can be as simple as an obscure setting hidden deep in the operating system, making them difficult to diagnose. However, if your computer is not behaving normally immediately after updating or installing a new application, you have an immediate starting point for investigation.
Common signs that often indicate software problems include:
- Error message: Periodic pop-ups, such as “app not responding”, may indicate that the software is corrupted.
- Slow performance: A slow system can be caused by junk software, malware or software that is not working properly taking up system resources.
- Startup problem: Problems loading the operating system often stem from corrupted or unsuccessfully updated system files.
- The application crashed: Programs that frequently freeze or close unexpectedly are often software related.
- Connection problems: Difficulties with Wi-Fi, Bluetooth or the network may stem from incorrect settings or outdated drivers.
- Driver problem: Outdated or corrupted drivers can cause errors.
The complexity of the software layers of modern systems can make troubleshooting difficult. However, reinstalling troublesome apps or checking for updates is usually all that's needed.
Troubleshoot and determine root cause

The above diagram is not a complete list of necessary steps. However, it represents a systematic approach that will be effective in many cases. Below, the article has broken down key steps that can help you diagnose the root of the problem and hopefully assist in resolving the issue.
- Perform a visual inspection: This is especially useful if the machine does not power on, but this is not the only case. Start with the power cable and power supply (you can check the laptop power supply with a multimeter). Also, check if the cooling fan is working effectively. Even when the fan is running, the heatsink can still get dirty and needs cleaning.
- Run the Diagnostic Tool: There are many diagnostic tools available to verify the health of your computer. While many of these tools are designed for Windows systems, there are also good diagnostic tools for Macs that can help Apple users.
- Boot into Safe Mode or equivalent: Safe Mode skips loading unnecessary drivers and software. While it's not certain, the general rule is that if your machine boots into Safe Mode, the problem is likely software-related.
- Update drivers and software: Outdated drivers and failed updates are on the list of common suspects when it comes to computer problems. Just like diagnostic tools, there are many free driver update utilities that can help here.
- Reinstall the operating system: This is one of the surest ways to identify hardware problems. From experience, installing an operating system is rarely effective in cases of hardware malfunction. Of course, this will also resolve any existing software issues. However, always ensure that your system is fully backed up and your data is safe before proceeding.