Computer Support for Northumberland
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Why is my computer so slow?

Posted on: 17th July, 2019

Clients often ask this question, “Why is my computer running so slowly?”

The answers are as many and as varied as there are computer models in existence! But let us consider the most likely reasons for this problem.

Dell laptop motherboard

How old is your computer?

If your computer is over 5 years old, there’s the most likely reason for your problem.

Computers are designed to last a certain amount of time, with cheaper models being made from cheaper components, and so lasting less time than more expensive makes.

This may seem obvious, yet most people buy the cheapest computer that they can, without wondering why much more expensive computers are available. But, as a very rough guide, a £350 computer is designed to last 3 years, whereas a £500 computer is made to last 5 years. (Better computers can cost you less in the long term!)

If I am asked to repair a computer I am unlikely to accept the job if the computer is older than 5 years. The cost to the client simply isn’t worth it. They are probably better placed investing their money in a new computer.

Why do older computers run slowly?

This problem is much more apparent in a laptop than a desktop, although both types of computer are affected to varying degrees. It is down to the cooling ability of the 2 different types of PC.

When the computer is switched on it warms up. When it is switched off, it cools down. It is this cycle that causes the components, and especially the motherboard, to flex. The soldered joints and circuits degrade with that flexing, and so become less efficient over time. (This is the same effect as we see on older roads, where potholes appear in degraded roads, causing the traffic to run ever more slowly.)

Is your computer too hot?

This is often a problem seen more in laptops than desktops, but does affect both types of computer.

Laptops have smaller cooling fans and less ventilation ability. The vents are usually in the bottom of the case, so using the laptop on your lap, or on the duvet, will block the cooling air. As the processor heats up it will deliberately slow itself down, as a form of thermal protection. It will eventually switch itself off!

Desktops which are pushed under the desk and never see a vacuum cleaner will become clogged with dust, which makes the cooling fans much less efficient and can stop them altogether. The usual sign is a noisy computer, as the fan struggles to keep up with demand for cooling air.

Hot computers run more slowly by design.

Is your Hard Drive too full?

Windows requires around 10% free space on the computer hard drive, simply for it to work efficiently. If you open “My Computer” you can see the amount of free space on the main drive. If this is shown as a red line – as in the picture below – the hard drive is way too full and will not be working as well as it should.

Full C Drive

You can right-click the drive and choose “Properties” from the menu that drops down. Look for “Disk Clean Up” which allows you to choose which files to delete, (this does not delete your own data). You could also delete “System Files” that are no longer required, to free up more space.

Too much software?

Modern computers are designed to run multiple pieces of software all at once. This efficiency allows you to multi-task to your heart’s content, or it should do so. Unfortunately some software, especially anti-virus programmes which run in the background, can hog a lot of computer resources, which means that it slows down.

Computer Support - Keeping IT Simple

Lots of software is designed to open as fast as possible. To achieve this it can start itself running in the background when Windows boots up, just so that when you wish to use the software it appears very quickly. But, if you have a few such programmes all running in the background, they can take up vital resources.

Removing such software from start-up is too involved for this blog, but give us a call and we can discuss how you would do this.

Insufficient memory

Windows uses the computer’s memory to move data around as it needs to. If the computer has too little memory then Windows becomes inefficient. It is true that Windows 10 is much more efficient than previous versions of Windows and is usually happy with 4 GB of memory.

But a memory upgrade is usually a cheap and efficient way to speed up a computer. Having said that, the speed of the computer is down to the interaction between memory, processor, motherboard, hard drive and other components. A cheap & cheerful memory upgrade may make no difference if the other components are at fault.

You can’t have too much memory, but the law of diminishing returns does apply. For standard office type working you won’t see much difference once you have 8 GB of memory.

Failing hard drive

If the computer’s Hard Drive is starting to fail this is likely to become obvious through a slow down in the speed of the computer.

If you suspect a failing hard drive then you should be sure to be backing up all of your data as regularly as possible. (To be honest, you should do this anyway, even if the hard drive gives no cause for concern!)

Computer Hard Drive

It is possible that you can run diagnostic programmes to check the state of the hard drive, but these will vary for every make and model of computer. Search online for how to run such diagnostic tests on your own PC, or call us for advice.

Viruses & Malware

Computers infected with viruses or malware will not necessarily show any untoward symptoms. Some such software may not wish you to know that it exists, but could be using up valuable computer resources.

Always have a good, reputable anti-virus programme running, but choose one which doesn’t slow the computer down as well, of course! I recommend Webroot – fast, efficient and a very small “footprint”. ( )

You can also download the free, or paid for, version of Malware Bytes. This will happily run alongside Webroot. (

Windows & Drivers Updates

Keeping your computer updated is very important. Windows should be running the updates in the background, but this doesn’t always happen automatically.

Windows Updates

“Drivers” are small pieces of software that tell Windows what types of hardware components your computer has inside. It can be vital to keep drivers updated and you can download these for free from your computer’s manufacturer. Search online or call us for advice.

Registry Cleaning programmes

And finally, we come across a lot of very slow computers where the client has run one of the many “Registry Cleaner” or “Boost Your PC” type of programmes. Such “free” software keeps our business running! The chances of it damaging your computer is way higher than the possibility that it will do any good. We don’t use such software and we can’t recommend that you do so!

Free advice!

We offer free advice to any Northumberland based businesses that wish to take advantage of it. We’ll look at your existing computer systems and give free, frank and no-obligation advice on how you could improve your situation. Call now on 01670 432 324!

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Curlew Computers – based between Alnwick and Morpeth – offer computer support services to businesses, schools, charities and home users throughout Northumberland. We look after businesses with anywhere from 1 to 25 computers.
Computer Support Contracts; Secure Online Data Backup; Domain Name Hosting; Office 365 Solutions.

Call: 01670 432 324 or 0759 666 4626
Keeping IT Simple!

© Michael Donkin 2019