Your computer seems to be malfunctioning — it’s slow, programs are crashing or Windows may be blue-screening. Is your computer’s hardware failing, or does it have a software problem that you can fix on your own?

This can actually be a bit tricky to figure out. Hardware problems and software problems can lead to the same symptoms — for example, frequent blue screens of death may be caused by either software or hardware problems.

Computer is Slow

We’ve all heard the stories — someone’s computer slows down over time because they install too much software that runs at startup or it becomes infected with malware. The person concludes that their computer is slowing down because it’s old, so they replace it. But they’re wrong.

If a computer is slowing down, it has a software problem that can be fixed. Hardware problems shouldn’t cause your computer to slow down. There are some rare exceptions to this — perhaps your CPU is overheating and it’s downclocking itself, running slower to stay cooler — but most slowness is caused by software issues.

Blue Screens

RELATED: Everything You Need to Know About the Blue Screen of Death

Modern versions of Windows are much more stable than older versions of Windows. When used with reliable hardware with well-programmed drivers, a typical Windows computer shouldn’t blue-screen at all.

If you are encountering frequent blue screens of death, there’s a good chance your computer’s hardware is failing. Blue screens could also be caused by badly programmed hardware drivers, however.

If you just installed or upgraded hardware drivers and blue screens start, try uninstalling the drivers or using system restore — there may be something wrong with the drivers. If you haven’t done anything with your drivers recently and blue screens start, there’s a very good chance you have a hardware problem.

Computer Won’t Boot

RELATED: What to Do When Windows Won't Boot

If your computer won’t boot, you could have either a software problem or a hardware problem. Is Windows attempting to boot and failing part-way through the boot process, or does the computer no longer recognize its hard drive or not power on at all? Consult our guide to troubleshooting boot problems for more information.

When Hardware Starts to Fail…

Here are some common components that can fail and the problems their failures may cause:

  • Hard Drive: If your hard drive starts failing, files on your hard drive may become corrupted. You may see long delays when you attempt to access files or save to the hard drive. Windows may stop booting entirely.
  • CPU: A failing CPU may result in your computer not booting at all. If the CPU is overheating, your computer may blue-screen when it’s under load — for example, when you’re playing a demanding game or encoding video.
  • RAM: Applications write data to your RAM and use it for short-term storage. If your RAM starts failing, an application may write data to part of the RAM, then later read it back and get an incorrect value. This can result in application crashes, blue screens, and file corruption.
  • Graphics Card: Graphics card problems may result in graphical errors while rendering 3D content or even just while displaying your desktop. If the graphics card is overheating, it may crash your graphics driver or cause your computer to freeze while under load — for example, when playing demanding 3D games.
  • Fans: If any of the fans fail in your computer, components may overheat and you may see the above CPU or graphics card problems. Your computer may also shut itself down abruptly so it doesn’t overheat any further and damage itself.
  • Motherboard: Motherboard problems can be extremely tough to diagnose. You may see occasional blue screens or similar problems.
  • Power Supply: A malfunctioning power supply is also tough to diagnose — it may deliver too much power to a component, damaging it and causing it to malfunction. If the power supply dies completely, your computer won’t power on and nothing will happen when you press the power button.

Other common problems — for example, a computer slowing down — are likely to be software problems.

It’s also possible that software problems can cause many of the above symptoms — malware that hooks deep into the Windows kernel can cause your computer to blue-screen, for example.

The Only Way to Know For Sure

We’ve tried to give you some idea of the difference between common software problems and hardware problems with the above examples. But it’s often tough to know for sure, and troubleshooting is usually a trial-and-error process. This is especially true if you have an intermittent problem, such as your computer blue-screening a few times a week.

You can try scanning your computer for malware and running System Restore to restore your computer’s system software back to its previous working state, but these aren’t  guaranteed ways to fix software problems.

The best way to determine whether the problem you have is a software or hardware one is to bite the bullet and restore your computer’s software back to its default state. That means reinstalling Windows or using the Refresh or reset feature on Windows 8. See whether the problem still persists after you restore its operating system to its default state. If you still see the same problem – for example, if your computer is blue-screening and continues to blue-screen after reinstalling Windows — you know you have a hardware problem and need to have your computer fixed or replaced. If the computer crashes or freezes while reinstalling Windows, you definitely have a hardware problem.

Even this isn’t a completely perfect method — for example, you may reinstall Windows and install the same hardware drivers afterwards. If the hardware drivers are badly programmed, the blue-screens may continue.

RELATED: Beginner Geek: How to Reinstall Windows on Your Computer

Blue screens of death aren’t as common on Windows these days — if you’re encountering them frequently, you likely have a hardware problem. Most blue screens you encounter will likely be caused by hardware issues.

On the other hand, other common complaints like “my computer has slowed down” are easily fixable software problems. When in doubt, back up your files and reinstall Windows.

Image Credit: Anders Sandberg on Flickr, comedy_nose on Flickr

Profile Photo for Chris Hoffman Chris Hoffman
Chris Hoffman is Editor-in-Chief of How-To Geek. He's written about technology for over a decade and was a PCWorld columnist for two years. Chris has written for The New York Times and Reader's Digest, been interviewed as a technology expert on TV stations like Miami's NBC 6, and had his work covered by news outlets like the BBC. Since 2011, Chris has written over 2,000 articles that have been read more than one billion times---and that's just here at How-To Geek.
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