9th May 2008

PC buying guide - How to choose a new computer

Welcome to the helpwithpcs.com cheap computers section,

Welcome to our PC buying guide.

In this section you will find a PC buying guide and a selection of new, refurbished,
and off-lease computers at a price to suit any pocket.

Buying a PC can be a bit of a daunting experience, especially if you are not sure about the type of PC you need, hopefully this buying guide will give you that extra bit of knowledge required to make the right choice.

The first thing you need is a general idea of what a PC contains and what each component does, this will help you decide which components you need for your PC.

Below is a brief description of the parts that the average computer contains:

Click component for more details:

Motherboard
Processor
Memory (ram)
Sound card
Graphics Card
Hard Drive

Modem
CD ROM
CD Writer
DVD ROM and Writer
Network Card
Monitor

Motherboard
This is the main circuit board of a PC, your motherboard will depend on your choice of processor (CPU).

Motherboards can come with various peripherals built in such as sound cards, modems and graphics cards.

Onboard Sound Cards - The sound cards that are built in will suffice in most circumstances unless you want extra inputs or outputs like surround sound for instance.

Onboard Graphics Cards - If you buy one with a graphics card built-in then make sure it has an AGP (Accelerated Graphics Port) slot as well or you may not be able to upgrade your graphics card in the future. Also onboard graphics cards normally use the systems memory instead of their own so it can slow down the system if you don't have sufficient RAM (Random Access Memory).

Onboard Modems - The modems that are built in are normally 56K standard modems and will suffice for most uses, unless you want an ISDN (Integrated Services Digital Network) or ADSL (Digital Subscribers Line) modem.

Processor
This is the brain of your computer, and has a very dramatic effect on the speed of the entire system. It's wise to go for the best processor your budget can afford. The performance of processors is measured in MHZ or GHz, with GHz being 1000 MHz, obviously the faster the better. The Pentium 4 is now becoming the standard along with the AMD equivalent (AMD Athlon).

Memory (RAM)
(Random Access Memory) This is a very important part of your PC, 256Mb (megabyte) is the minimum you should look for. If your motherboard has an onboard graphics card then it might be wise to go for a bit more memory (RAM) like 512Mb due to the fact that your graphics card will be using some of your main memory (RAM).

Insufficient memory will slow down your PC when using powerful programs due to the fact that the PC will use Virtual Memory, which is a technique of utilising hard disk space for memory, hard disks have a slower access time than memory, therefore affecting performance. All of the cheap computers featured on this page (like most PCs) are easily upgradable. For more information on RAM click here.

Sound card
This controls the sound in your PC, for instance if you were going to use the PC for musical purposes or you wanted a DVD player then you may want a good sound card with surround sound, also they come with various inputs and outputs so think about what you will want out of your PC in the way of surround sound or digital recording facilities.

Graphics card
This is the card that controls the quality of the graphics displayed on your monitor, so if for instance you were going to use the computer for powerful graphic applications (Graphical games, Computer Aided Design, etc) then you would want a decent graphics card, the standard now is an AGP graphics card with around 64Mb of onboard ram.

If your motherboard has an onboard graphics card then you can change the amount of memory that is assigned to it using the setup utility on your motherboard (sometimes known as the CMOS settings).

Some graphics cards have TV outputs allowing you to connect your PC to your TV, this is handy if you have a DVD player !

Hard Drive
This device is where you will store most of your programs and data, with software becoming ever more complex it is best to go for one of at least 40Gb (if it's a new machine then at least 80Gb). There are also different types of hard drive, IDE (Integrated Drive Electronics) and SCSI (Small Computer Systems Interface), the latter being faster but more expensive. Most users will find IDE more than ample in the way of speed. there are different models which have different RPM (Revolutions Per Minute) speeds, the standard is 5400RPM, but you can also get 7200RPM and faster, obviously the faster the better, but they can get expensive. For more information on hard drives click here, also see our guide to cheap hard drives.

Modem
This is the device that connects to the telephone line and controls your connection to the internet, normally the average 56K modem will suffice, this will transfer theoretically a maximum of 7 Kilobytes a second (with a perfect phone line and server !).

if you have an ISDN or ADSL internet connection then you will need to refer to your ISP to find out what type of modem you need.

For more information on modems click here.

CD ROM
These devices do not really make a dramatic effect on the performance of your PC only if you are constantly using them, but normally when you have installed anything from CD ROM it is normally accessed from the hard drive. If you go for one at 50X (that's 50 times faster than a normal CD) then it should suffice, it is best to go for a brand name for the sake of warranty. For more information on CD ROMs click here.

CD Writer
This device is used to record CDs, they come in various speeds, the speed depicts how fast they can burn (write) CDs. For instance an 18X will write a CD 18 times faster than normal (74min CD in just over 4 mins), also you can get rewritable cd recorders (which most of them are), with these you will often see them advertised as 18X-6X-40X, this means it will burn (write) at 18X, ReWrite (write again over an existing rewritable CD) at 6X, and read at 40X. If you are considering buying one then go for a brand name, and if it's possible go for a medium to top of the range model.

The average speed now is around 52x-32x-52x and they usually come with bundled software for burning (writing) CDs.

If you are looking to buy a CD Writer separately, see our guide to cheap cd writers.

DVD ROM - DVD Writer
DVD ROM drives can be used to watch DVDs on your computer, they are advertised as having different read speeds, try and go for one in excess of 8X as this can help keep the image smooth. If you combine it with a graphics card (see above) that has a TV output then you can link your PC to your TV and watch DVDs on your big screen.

DVD Writers (DVD-R/RW) allow the home user to back up any old video, or create back-up copies of DVDs. DVD Writers are often advertised as 4X-4X-12X, this means it will burn (write) at 4X, ReWrite (write again over an existing rewritable DVD) at 4X, and read at 12X the normal DVD speed.

Network Card
An inexpensive device that is used to link 2 or more computers together, the average home computer will not require this device, although some broadband internet connections require a network card (check with your internet provider as they normally supply this component if required).

Monitor
This is really down to personal preference, 17" is a good size although if you are going to be sitting close to the screen then 15" should suffice. TFT screens are handy when space is a problem, although they can be expensive, another thing to consider would be the dot pitch but they are all fairly similar these days.