Computer Buying Guide

How Do They Work?
Your computer will run a number of specialised programmes, also known as 'applications'. Each is designed to perform a particular set of functions, such as word processing or editing pictures. These programs are supported by the computer's operating system, the software that controls many of the computer's functions; examples of operating systems include Microsoft's 'Windows' and Apple's 'Mac OS'. The brain of the system, on which the operating system runs, is the CPU (Central Processing Unit), the computer's central chip or microprocessor.

What To Look For
With such a wide range of computers to choose from, asking yourself the following questions will help narrow the field:
• What do you want to do with your computer? (Consider what you might need in future, not just what your current needs are.)
• What software will you need to run - now and in future?
• Will the processing you need the computer to do be very complicated?
• Do you want a large monitor? Should it be a flat screen monitor?
• Do you want to connect to the internet or send emails?
• How much memory do you need for current and future uses?
• Does the software you want to run require a video and/or sound card?
• What external devices do you want to be able to connect to your computer? How many ports will you need to do this, and do you know what type you need?
Once you have this information, consider these points.

Operating system - Windows PC or Apple Mac?
The operating system controls many of the computer's functions and also acts as an interface between the user and the microprocessor. There is a perennial debate over whether it is better to purchase an Apple Macintosh ('Mac') or a PC ('personal computer'). Both systems have their strengths and weaknesses and both have their fans.

Both Macs and PCs can perform most tasks well. While strong pieces of software have originated on each individual platform - e.g. Adobe PhotoShop on the Mac - they have generally migrated across to the other. They do have their particular areas of strength, though. It is often argued that Macs have the upper hand when it comes to the use of graphics-based applications, which is why they are used so widely in sectors such as education and publishing. By the same token, PCs are frequently regarded to have the edge when it comes to running admin-based day-to-day business applications. They are also more widespread amongst home users so compatibility is less of an issue.

Speed and type of processor
The Central Processing Unit (CPU or 'processor') is the 'brain' of the computer that drives and controls all its functions.

There are a number of different processors. PC users have the choice of chips from a number of manufacturers. Market leader Intel offers the entry-level Celeron chip, or the latest Pentium IV, which is well equipped to handle the latest graphics and gaming programs. Other, equivalent chips are supplied by AMD - the high-power Athlon or the less-expensive Duron. Apple computers are normally are supplied with Motorola processors.

Memory
You will need to consider the amount of hard disk space your computer will need, and the amount of Random Access Memory (RAM).

A computer's hard disc - also known as its hard drive - is the space where programs, files, data and documents are stored. Hard discs come in different sizes, measured in gigabytes (GB). Aim to buy at least 40GB of hard drive space, the more the better, particularly if you will be using programs that use a lot of disc space, such as images or MP3 files. Hard discs operate at different speeds. 5400RPM is the standard, suitable for most uses. The extra speed of the faster 7200RPM drive helps access data quickly and is particularly good for video editing and software heavily dependent on graphics.

Random Access Memory (RAM)
Also known as 'on-board' memory - RAM is used for processing and storing the data that the computer is currently working with. To operate efficiently a computer must have sufficient RAM otherwise it will run too slowly. RAM is measured in megabytes (MB); 256MB should suffice for most applications or tasks. There are three types of RAM. SDRAM is the standard, basic variety found on most entry-level and mid-price computers. DDRAM (Double Data Rate RAM) is twice as fast as SDRAM; and the top-end RDRAM is faster still.

Other points to consider

Ports
In order to be able to connect and communicate with other devices and to send and receive various types of information, a PC needs a number of input and output channels, known as ports. You will need to ensure your computer has sufficient ports, of the right type, for the accessories you intend to plug into it. There are a number of different types of port:
• Parallel - Typically used to connect to a printer or a scanner.
• Serial ports - Mostly used for connecting to external modems and handheld computers/PDAs.
• Universal Serial Bus (USB) - Another method of connecting printers, scanners and other USB peripherals like digital cameras and hand held computers.
• Firewire/IEEE 1394 - A very fast method of file transfer, much quicker than even USB speeds. To make use of this, both your computer and accessory will need a Firewire/IEEE 1394 port. This is essential when transferring video images to and from digital camcorders. Modem: Normally built into the computer, a modem allows data to be transmitted over phone lines via a conventional jack plug. It sends and receives data and fax transmissions, and connects to the internet for email and net browsing. Modem speeds are measured in kilobytes per second (Kbps). Most PCs come with a modem of 56Kbps. This is sufficient for most uses, but heavy users of the internet might want to consider obtaining one of the high-speed 'broadband' forms of internet access available. disc drives: Your computer will be fitted with one or more of the following types of disc drives for reading and, occasionally writing to, discs:
• CD-ROM drive - The CD-ROM drive reads CDs containing new computer programs, as well as playing music. The drives operate at different speeds.
• CD-RW drive - this is able to 'write to' (record onto) a blank CD, as well as reading it. This can be useful for recording music from MP3 files or CDs, subject to copyright. It is also a useful device to store a large amount of data.
• DVD (Digital Versatile Disc) ROM drive - A format which stores higher data storage capacity than a CD-ROM drive - up to 4.7 gigabytes of data. DVD ROM drives can play films as well as reading CDs.

Upgradeability
If you think you are likely to need to increase the computer's memory or processor in due course, check that the computer will support upgrades. Many PCs can be upgraded, it is worth checking if this is so.

Software
The majority of desktop computers come pre-loaded with some software, including an internet browser and email program - eg. Microsoft's Explorer and Outlook Express. Programs offering word processing, spreadsheet and other basic administration tasks are particularly popular - eg. Microsoft's Works package. The more comprehensive Microsoft Office suite is normally available to buy separately.

Monitor
The computer's display screen will either be supplied with the computer, or be available as a separate purchase. The choice is between a conventional Cathode Ray Tube (CRT) and space saving liquid crystal display (LCD) monitors. LCD monitors are becoming increasingly popular.

What Are The Minimum Requirements
With such a wide range of models, prices and functionality on the market, it can be confusing to select exactly the right computer. Unless your needs are particularly specialist, the following specification will handle most people's computing needs:
• For a PC, a 600MHz processor - either a Celeron or a Pentium IV. For Macs, a G3 of 400MHz.
• 17" monitor
• High speed CD-ROM 32x minimum for playing computer games • 256MB of RAM memory
• 40GB of hard drive space
• 1.44MB 3½" floppy disc drive • 56Kbps modem • 2USB ports in addition to the standard ports for keyboard, mouse, printer etc.
• Sound card - 16-bit will provide adequate sound, 32-bit produces a richer, fuller effect. Speakers, headphones and microphone are optional
• Video card with at least 16MB of RAM (or 64MB for playing games)
• Basic software, sufficient for your needs

How much money should you spend on a PC or Apple Mac? The decision mainly will hinge upon what you intend to do with it. For word-processing, spreadsheets and internet use, an entry-level or mid-priced computer will normally suffice. If you will be playing the latest computer games or running graphics programs then you will need more memory and disc space, and a faster processor, which will require a higher-priced machine. Bear in mind that a more expensive computer will be more likely to run the latest software, and that a cheaper model may need to be replaced more frequently.

We hope you found this computer buying guide useful. Reprinted from an article supplied by John Lewis