How to repair a dying PC

If you can recognise the tell-tale signs that your PC’s health is failing, you have a good chance of being able to remedy the situation with little upheaval. The difficult part is recognising where the problem lies, since it isn’t often obvious which component or part of the operating system is misbehaving. On these pages we show you how to identify some of the most common technical problems, and how you can resolve them.

Software vs hardware

When a computer isn’t behaving properly, the first task is to work out whether it’s the hardware or software that’s at fault. This isn’t an exact science, but a major clue is whether or not Windows throws up the notorious “blue screen of death”. If you see a blue error screen appear momentarily before your PC restarts, it indicates that Windows detected a problem and was able to shut down the system in a managed way. This wouldn’t have been possible if, for example, your CPU or hard disk had abruptly failed – so the presence of the blue error screen suggests that your system has a software problem.

In this context, “software” probably doesn’t mean applications and games. Windows is designed in such a way that it’s usually impossible for regular programs such as these to crash the whole system. When we talk about software faults, we principally mean within Windows itself. Although the core OS is impressively stable, third-party device drivers are easily able to take down your system. If your problem is a faulty driver, you may be able to identify it simply by watching what happens when things go wrong: for example, if your computer crashes every time you try to change screen resolution, there’s a good chance that your graphics driver is to blame.

The information shown on a blue screen may provide a lead too, but by default it doesn’t appear on screen for long enough to be legible. You can make it remain visible until you reboot by opening the System Control Panel item, clicking on Advanced system settings, choosing Startup and Recovery, and unticking the “Automatically restart” box. The next time your computer crashes you’ll be able to read the information at your leisure: you may see a reference to a particular file such as atikmdag.sys or nvlddmkm.sys. You can look up this file on the web to work out what it is – in these cases, the letters “ati” and “nv” give strong clues that they relate to ATI or Nvidia graphics card drivers.

If it’s a dodgy driver that’s causing system instability, you have plenty of options. Check the manufacturer’s website for an updated version of the driver, as the problem may have been fixed. Alternatively, you can try installing an older version of the driver, either by again going to the manufacturer’s website or by right-clicking on the device in Device Manager and selecting Driver | Roll Back Driver. If you have the option, look for a driver certified by WHQL (Windows Hardware Quality Labs). This tells you that Microsoft itself has tested the driver on a wide range of hardware.

If switching drivers doesn’t help, it’s possible the driver failure is being caused by an underlying problem with the hardware. In this case, we’re afraid there’s no simple solution, short of replacing the device – or, if it’s built into your motherboard, disabling it in the BIOS or from the Device Manager.