Computer running slow?

Note: Although this article refers to desktop computers, it still generally applies to laptop computers as well.

The single biggest complaint our users have when posting their problems here, across all brands and all models, can be summed up in three little words: Computer running slow! It has been affecting computers for years, but the causes have not changed considerably in that time. I'm going to keep the language as simple as I can in this article, so if you consider yourself pretty tech-literate, you might want to skip ahead to the advice section below.

The main factors in a computer running slow are the programs that are running on it, the age or power of the computer itself and the Operating System (i.e. Windows). In order to how to speed up your computer, you might want to think about these things.

How old is the computer, and what do you use it for?

A lot of people use their computers for simply web browsing and emailing and basic computers have historically been fine for this. However, modern computer usage is changing. People are using their computers to watch high definition videos on YouTube, BBC iPlayer, Hulu and more. A basic computer won't give you the smooth experience you might hope for without a little help.

How do I know how good my computer is?

Time for a one-minute crash course in computer parts. There are four main parts inside a computer that can affect the speed of your computer: the Processor, the Memory (or RAM), the Hard Drive (or Hard Disk) and the Graphics (sometimes referred to as Graphics Card or GPU). Other things are not likely to affect performance as much, so let's not worry about them.

How to understand these things easily: Think of your computer as a little office containing a little man, working hard to do whatever you ask him to.

He is the Processor (sometimes called the CPU). Everything goes through him. You ask him to do things for you and he'll tell you when they're done. His 'speed' tells you roughly how quickly he can get things done. If you have a 'dual-core' processor, this basically means that you have a team of two little men in your office instead of one. 'Quad-core' means you have four little men.
In a nutshell: the CPU speed essentially shows the top speed at which your computer works

The office has desk space, on which your little man puts all the things he is working on at the moment. If you ask him to do two things, he'll put both of those things on his little desk and try to work on them both at the same time. So if you want him to work on lots of things at the same time, he's going to need a lot of desk space. The desk space is the computer's Memory.
In a nutshell: more Memory means the computer can be working on many different things at the same time

The office also has lots of shelf space. The shelf is where we keep things such as files, photos, videos, folders, games, music and so on - just like in a normal house or office. When the little man needs to use these things, he gets them down from the shelf and works with them on his desk. When he's finished using them, he puts them back on the shelf. If he has bigger shelves or more shelves, he can keep more photos, videos and so on. If the shelves are disorganised, it will take him much longer to find things. The shelf is the computer's Hard Drive.
In a nutshell: a bigger Hard Drive means you can store more things

Finally, we come to the Graphics. Computers use screens to show us what they're working on right now. The only way for the little man to communicate with us is by drawing tens of pictures a second, like in animation. As you can imagine, this puts quite a strain on the little man, but he puts up with it and to be honest, he doesn't usually bat an eyelid. However, some computers have a Graphics Card - a separate computer part that is responsible for all of the drawing tasks. Think of it as a live-in artist to take the strain of drawing off the little man. The artist is a professional and she can draw much better than the little man can.
In a nutshell: if your computer has a separate graphics component, it will be much faster at visual tasks such as 3D games and HD video

OK, so we understand the parts. Now we can understand why they might be the cause of your computer running slow. Computers are always improving and getting better, so the apps and software we run on them get bigger, better and faster too. They need faster processors, more memory and more hard disk space.

Processor: If your Processor (i.e. little man) is old, inefficient or slow, it will make general tasks slower. The Processor is the heart of the computer and cannot be easily replaced.
Memory: If your computer doesn't have enought memory (i.e. desk space), it can't work with big apps that take up lots of desk space or multiple apps at a time. You can solve this by buying more memory (i.e. more desk space) - up to the limit that your computer will allow.
Hard drive: If your computer doesn't have much hard drive (i.e. shelf) space, you won't be able to store everything you want to. However, this is not the only problem with this. If the hard drive (i.e. shelf) space is running very low, it means the Processor (i.e. little man) has to put things back wherever he can find a space rather than where they should be. This make the hard drive (i.e. shelf) very disorganised and significantly reduces speed.
Graphics: If you want to play modern games, you'll need a dedicated Graphics GPU (i.e. artist), as the Processor (i.e. little man) can't cope with all that drawing by himself. If you're not going to bother with games, you probably don't need this.

How do I know what's inside my computer?

Press the Windows key (between 'Ctrl' and 'Alt'), type 'computer' and press Enter. A window should open on your desktop. Click the right mouse button on a blank area in that window and select 'Properties' to see the Processor speed (measured in GHz) and the Memory (measured in GB). In the window from before, right click on your Hard Disk (it typically says 'C:') and again select 'Properties' to see how much free space you have on your Hard Drive.

The golden question: How good a computer do I need?

Everyone's needs vary, but for modern computing (2014) I would recommend the following as a minimum:

Component For basic email, browsing and writing documents For smooth browsing, MS Office, and online video For photo editing and light games For games at PS4/X-Box One standard and poweful software applications
Processor
Single core, 1.6Ghz
Dual core, over 1.8Ghz
Dual or Quad core, over 2Ghz
Dual or Quad core, over 2Ghz
Memory
2Gb
4Gb or more
8Gb or more
8Gb or more
Hard Drive
At least 20% free space
At least 20% free space
At least 20% free space
At least 20% free space
Graphics
Not needed
Probably not needed
A cheap (under £40) GPU would be beneficial
A decent (over £80) GPU is required
Example Computer
Desktop: n/a
Laptop: n/a
Desktop: about £300
Laptop: about £330
Desktop: about £350
Laptop: about £399
Desktop: about £550
Laptop: about £999

I would almost never recommend the lowest level of computer here. It might be OK in the short term, but it is probably very much a false economy, and spending a little more for the next level up would mean your computer is likely to last longer, making it cheaper in the long run. Remember that some desktop computers might not include a monitor, keyboard or mouse, check these before you buy.

Do I need to upgrade Windows to stop my computer running slow?

Update, yes. Upgrade, not necessarily. Updating is free - press the windows key, type update and see what updates you can install. Always keep your computer updated. Paying to upgrade to the latest version of Windows (Windows 8.1 at the time of writing this) is not likely to significantly increase speed unless you erase everything on your computer and start again.

What other advice do you have for a computer running slow?

You MUST have virus protection installed on your computer. Modern versions of Windows (Windows 8+) have a basic level of virus protection pre-installed, but for everyone else, you simply must have virus protection installed. You don't have to pay for it and it will prevent your computer from being infected with viruses that, at best, are causes for your computer running slow and at worst after your personal and credit card information. Check out Kaspersky or Norton for popular paid for virus protection, or AVG or Malwarebytes for free software (they'll recommend that you pay, but you don't need to pay to use their free software).

How about upgrading my computer?

Yes, upgrading your computer will improve performance. However, I only recommend the following upgrades - more than these, and you're better off just getting a new computer:

  • Upgrade the Hard Drive to an SSD: This will improve speed dramatically. SSDs (Solid State Drives, which means they have no moving parts) are coming down in price and will make your computer start up much faster and improve speed across the board in Windows. Typical prices start at around £40.
  • Upgrade the Memory: It's so easy to do. Turn your computer off, open it up, plug the memory in, close your computer. You should see speed increases instantly. There are lots of different kinds of memory, so check out this memory checker to see what kind of memory you need for your computer.
  • Buy a Graphics Card only if you want to play games: without one, only basic games will be open to you. A cheap card will cost you around £40 and will be sufficient to play many modern games at low to medium settings, but if you want the best performance, try spending north of £80. It can be difficult to know what Graphics Card is best, so resources like this can really help you out.
Keep your Hard Drive tidy

You should keep your hard drive tidy and well organised. That doesn't mean you need to manually go through and tidy it, you just need to check it for errors and if it is a regular (not SSD) drive, defragment it. Defragmenting means putting things back where they should be so the computer doesn't have to waste time looking for them. A good defragmenter is Smart Defrag and it's completely free. Don't pay for a defragmenter.

Spot a fault

If your computer is suddenly performing much more slowly, there may be a hardware fault. Typically, the Hard Disk or the Memory might fail in a computer. You can check to see if you have failing parts by running this hard disk checker and Windows memory tester (press the Windows key and type mdsched.exe). If you have a memory failure, think of it like a broken desk - at any time while you're working, the leg could give way and you'll lose everything you're currently working on. Think of a hard drive failure as a slow burning fire on one of your office shelves. If you don't back up (make copies of) everything that's on that shelf right now, you will lose it all at some point.

Pay particular attention if your computer doesn't sound right. Clicking sounds can foreshadow impending doom.

Back up your files

I can't stress this enough. I know how much of a pain it is, but you simply have to back up anything that is valuable to you. Buy an external hard disk (like this one) and make copies of all your work, precious photos and anything else that you value on your computer. Do it now. I'll wait.

Get rid of unnecessary software and apps that start up every time you start up

Your computer running slow may be a symptom of having lots of programs installed that you don't use. Either uninstall these programs (press the Windows key and type 'add or remove programs') or disable them at startup (press the Windows key and type 'msconfig', select "Startup" at the top).

Keep the registry tidy

Sounds difficult, but the registry is just your computer's record of what's on your computer. As time goes on, you add, remove or change things that don't always get recorded in the registry, so Windows thinks that something exists when in reality it's long gone. Running a registry cleaner such as Piriform's excellent CCleaner can prevent your computer running slow due to registry errors.

Be a friend to your computer

Take good care of your computer. Don't move it around when it's on, don't cover the vents and don't hit it, bash it or bump it. All of these things can damage components to the point where you notice your computer running slow.

Anything else?

I know it sounds patronising, but try not to get frustrated with your computer. If it isn't doing what you want, remember you can always ask Google for help.

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