What is RAM? How it affects your computer’s performance

Everything you need to know about this vital computer spec.

While computers have become a lot easier to use in recent years, there are still a lot of confusing terms to get to grips with. One of them is RAM.

Here we’ll explain what RAM is, how it works and why you need to know about it.

[Read more: How to clean up your PC]

What is RAM?

RAM stands for Random Access Memory, and is also known as main memory, primary memory or system memory. It’s a hardware device inside your computer that lets information be stored and retrieved. Generally speaking, the more RAM you have, the quicker information can be stored and accessed, and the quicker your PC will be able to perform tasks.

How does RAM differ from ROM?

ROM stands for Read-Only Memory. This is memory that can only be read – for example, a cartridge used with video game consoles which lets them run games. The main difference is that RAM is volatile – this means it needs power in order to keep the data accessible. The minute you switch your computer off, the RAM is wiped and all the data is lost, whereas the data in ROM remains, even when the system is powered down.

How does RAM differ from hard disk space?

Data stored on a hard disk or CD is stored sequentially, whereas in RAM it is stored randomly. This means that a computer can access data from within the RAM much quicker than from a CD or hard drive.

How does RAM work?

When your computer boots up, the operating system and drivers are loaded into memory, letting the central processing unit (CPU) to speed up the boot process. Once it’s loaded, each programme you open is loaded into memory. Open a lot of programmes, and the computer will swap the data in the memory between the RAM and the hard disk drive. Hence the more memory you have, the quicker your computer will operate.

How much RAM do you need?

It depends on what you’re doing. If all you’re doing is browsing the web, sending emails and writing the odd Word document, 2GB should be plenty. If you watch a lot of video online and make video calls, 4-6GB is advised, while if you’re playing processor-intensive games, 8GB or more should suit you.

Can you add more RAM?

You can. Most tower PCs have slots for installing more RAM, but check they’re compatible before you splash the cash - RAM upgrades come in RIMM, DIMM, SIMM and SODIMM varieties, depending on the number of connecting pins they have and their compatibility with other components on the computer's CPU. For laptops, you're better off getting it done professionally, unless you're confident tinkering under the bonnet of your machine. Before you do, check it doesn't invalidate the warranty, or you could be in trouble should something go wrong.

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