Monitors + Displays : The CCL Guide
Computer Monitor Buying Guide
Are you unable to decide which TFT monitor will suit you best? No idea how much money you should be forking out?The aim of this guide is to explain the differences between various types of monitor, to examine the options you have, and to give you an idea of how much you should be spending.
Basic Information
- Almost all monitors now sold are flat-panel displays. They are thinner and consume less power than the older CRT technology (see 'Monitor Types').
- Computer monitors typically connect to the back of you computer using one of two standardised connectors (see 'Connectivity').
- If your computer has more than one of these connectors, it should allow you to use more than one monitor at a time.
- TFT Monitors are available in various sizes, commonly measured diagonally in inches.
- You should expect to pay at least £80 for a new monitor. If you're looking for a monitor for home use, you should be considering a price range of £100 - £200. Highest-end models can demand much more.
Which one should you buy, and how much should you expect to pay?
This depends on what you use your computer for...
- If you watch movies, you'll need a display with a fast refresh rate, high contrast, brightness and a large viewable area.
Sizes to consider: Widescreen 19" or larger
Key terms to look for: DVI, VGA, HDMI, HDCP, Component, HD-Ready, Response Rate / Refresh Rate, 720p, 1080p, Contrast, Brightness, Viewing Angle
Target price range: £110 +
- For office and general Internet use, a basic model with moderate to high resolution will suffice. Paying more will generally result in a model with improved readability of text and a larger viewable area. Widescreen TFT monitors of 22" or greater size will allow the display of two full-size A4 documents side-by side, which is very useful for publishing and office work. Some widescreen monitors will also pivot on their mount, allowing their use in a portrait format (great for web pages and documents).
Sizes to consider: 17" or larger
Key terms to look for: DVI, VGA, Contrast, Rotating / Pivoting
Target price range: £90 - £200
- If you play games, you'll want to find a large display with a high resolution, fast refresh rate and good black-levels. Monitors with sufficient resolution and suitable connections can be used with high-definition media players and modern games consoles like the Playstation 3 or Xbox 360.
Key terms to look for: DVI, VGA, HDMI, Response Rate / Refresh Rate, Contrast, Brightness, Black Level, 720p, 1080p
Target price range: £120 - £400
Monitor Specifications & Terminology
You'll see a lot of confusing terms when trawling through monitor specifications. Lets have a look at a few of the basics you should consider...
Monitor Types (CRT & LCD)
For some time now, flat-panel TFT monitors have dominated the market.
CRT computer displays are now only produced for specific purposes; mostly for professional use where highly accurate colour reproduction is required. Even these are now being supplanted by improved flat-panel technology that is capable of presenting more realistic colours.
LCD/TFT technology allows displays to be made much thinner, lighter, and far more efficient in terms of power usage than CRTs.
For the purposes of this guide, we shall only be considering flat panel displays.
Physical Size (15", 17", 19")
The first thing you'll probably see is the physical size of the monitor, as it is display in the product title. TFT monitors are measured diagonally across their viewable area (not their overall physical size). This measurement is most commonly given in inches, although you should be able to find exact (mm) dimensions within the detailed specifications.
Whilst there are a few odd sizes, almost all monitors fit into one of several standard groups:
- 15" (General Home Use)
- 17" (Office / General Home Use)
- 19" (Office / Gaming)
- 20" (Office / Gaming)
- 22" (Video Use / Gaming)
- 24" (Professional Use / High-End Gaming)
- 32" (HDTV Sizes)
Each of these sizes is also available in either Standard (4:3 or 5:4), or Widescreen (16:9 or 16:10) ratios. Note that sizes larger than 22" are only normally available in widescreen ratios.
Obviously, the wide ratio screens offer better viewing experiences when watching movies, however you should bear in mind that widescreen displays are not larger than their standard-ratio counterparts. Widescreen displays also sacrifice height in order to achieve the wider ratio, and don't actually offer a larger viewable area than standard monitors of the same advertised size.
Resolution
LCD monitors all feature a native resolution. That is, the physical number of pixels the monitor can display without scaling the image to fit.
You can use a lower resolution than your LCD monitor's native one. The image will either be centred in the display (with a black border around it), or will be stretched to fit the entire screen. This stretching results in a fuzzy image that is undesirable for most users.
Typically, LCD monitors of a certain physical size (See above) will have a corresponding resolution.
For example, standard 15" and 17" LCD monitors will normally have a resolution of 1024 x 768 or 1280 x 1024. Widescreen variations of these TFT monitors will have different corresponding resolutions, such as 1280 x 800 or 1440 x 900.
If you see a monitor that seems to have a lower resolution than others of the same size, it would be best to avoid it (see 'Dot Pitch').
Whilst the above resolutions will be sufficient for most users, professionals and gamers will seek screens with higher resolutions to increase their working space or visual quality. Increased resolutions demand a higher premium, and will also put more strain on your systems graphics hardware.
Response Rate / Response Time
LCD monitors suffer from a slight delay when changing from light scenes to dark ones. The pixels that compose the display are not capable of changing from light to dark instantly - they do this gradually over a period of several milliseconds. Good quality, high performance monitors will do this very quickly. Cheaper monitors will not, and the result will be a noticeable blur in scenes where the is high contrast and movement (eg. Games, Movies). The period of change from black to white (and back to black again) is referred to as 'response time'.
Lower response times mean less blur in high contrast scenes, and modern monitors now feature response times of well under 8ms, with no noticeable blur whatsoever. If you chose to purchase a monitor with 16ms or greater response times however, you should expect to see noticeable effects.
Connectivity
A computer monitor is connected to your PC with a single cable (although it is powered from the mains supply, not your computer). This cable will be one of two main types: VGA or DVI, or possibly a third newer type, HDMI.
Each of these provide varying levels of image quality on the monitor.
| VGA Older analogue connector, which should provide an acceptable picture on most displays of 19" or lower. This may depend on the quality of the cable and monitor. The image may need to be adjusted using the monitor controls in order to achieve acceptable results. DVI Newer digital connector, which provides excellent quality and requires no adjustment. HDMI The newest type of connector, only just starting to appear on high-end computers. Most commonly found on LCD TVs, but also starting to appear in computer monitors as a supplementary connector. Very similar image quality to DVI. |
Your choice of monitor may depend on the available connectors on your computer. If you only have the older VGA type of connector, you will need to look for monitors with a VGA socket. If your computer features the newer DVI connector, it is advisable to purchase a DVI-equipped monitor. Most monitors and graphics cards support the use of VGA to DVI adaptor cables in the event that you need to use a monitor with the wrong type of connector.
HDMI is a newer technology that is similar to DVI, and offers similar quality. Only high-end computers and modern laptops feature this connector, and very few computer monitors support it. When found on computer monitors, it is usually an additional connector intended for use with non-computer devices like games consoles and media players, but it may be used with computers where required. DVI to HDMI adaptors are available if required.
Modern graphics cards commonly feature a pair of VGA or DVI ports, which allows the use of two monitors at once.
Many monitors also feature two or three connectors - usually one of the VGA type and another of DVI variety. This allows you to connect multiple computers or other devices to the same monitor, so that you may easily switch between them without having to change the connections. Note that very few monitors support picture-in-picture functionality (as seen on some TVs).
Contrast & Brightness
These are both important factors when buying a monitor, and are especially important to gamers and multimedia users.
Brightness (or Luminance) is fairly obvious. It is measured in cd/m2 or candela per square metre. Higher values mean brighter white-levels.
Comparing monitors of otherwise similar specification and price will give you an idea of what brightness values to look for.
Contrast in monitors is measured as a ratio (eg. 700:1 or 1500:1). This is the 'difference' between the highest and lowest levels of light the monitor can produce (white and black). The higher the ratio, the better the monitor can handle games and films, where the may be numerous dark scenes with subtle detail. Again, comparing models in your price range will give you an idea of the Contrast Ratio you should be looking for.
Some manufacturers use dynamic contrast technologies, which adjust the monitors backlight in scenes which are overly light or dark. This works well when the entire scene is one or the other, but fails in instances where there are both extreme light and dark elements in a scene.
Note that manufacturers using this technology often quote misleading contrast ratios that use backlight adjustment to achieve unrealistically bright whites and dark blacks. This is called the Dynamic Contrast Ratio, and should be labelled as such. Where backlight adjustment is not used, it is called the Static Contrast Ratio. The two measurements are not directly comparable, so keep and eye out for the word 'Dynamic'.
Viewing Angles
Because of the nature of LCD technology, LCD-based monitors have limited Viewing Angles.
From directly in front of a monitor, you should see a 'perfect' image - that is, the best image that the monitor is capable of displaying. As you move away from the front of the monitor (left, right, up or down), you will notice the colours change and the contrast decrease. The angle to which you need to move to notice these changes is referred to as the Viewing Angle. Wider angles are preferable if you are likely to be looking at your screen from multiple positions, or often have multiple people looking at the same screen (from different angles).
Dot Pitch / Pixel Pitch
In very simplified terms, this is a measurement of the physical size (and spacing) of each pixel on the monitor, and is typically measured in millimetres. A smaller Dot Pitch is generally preferable to a larger one, as it typically means a sharper image.
Dot Pitch is largely dependant on the physical size of the monitor. For example, if you have two monitors - one 17" and another 19". Both have the same resolution (number of pixels) but one is physically larger, so the same number of pixels have to cover a larger area on the 19" monitor. Comparing the two monitors, you would most likely see a sharper image on the 17" model as a result.
It is generally better to look at the physical size and resolution of a monitor than to rely on Dot Pitch values.
By comparing a number of models in your price range, it should be obvious if a monitor has a resolution that is uncommonly low for its size (ie. it has a high Dot Pitch), and it should be easy to avoid such models.
Gloss / Glass / Matt Panels
There are a number of monitors available that feature special coatings and hard glass fronts, which are intended to improve the durability and image quality of the monitor.
You may see this feature advertised as X-Black, Color Shine, CrystalBrite, TruBrite or a number of other marketing terms. Apart from improving the overall look of the monitor, this also gives the impression of improved colours, black levels and contrast ratios.
A potential drawback of these models is their susceptibility to external light sources, which can cause glare and reflections on the screens. In controlled lighting environments such as offices, this isn't usually a problem. In situations where you need to use a monitor next to a window or other strong light source, it may be an issue for you.
Hard-Glass fronted displays offer similar benefits to the glossy panels, with the additional durability and protection of a solid fascia.
Normal LCD monitors may be easily damaged by applying pressure to the panel or by scratching the surface with a pen or similar instrument. Glass fronted monitors are not as easily damaged by such action.
Extras
Some TFT monitors come with extra multimedia features such as USB hubs, integrated webcams and built-in speakers.
Whilst hubs and cameras are considered to be useful features, integrated speakers generally aren't. The speakers included are often tinny, low-powered and of poor quality.
By all means look out for these extra features - but don't discount other models because they don't have them. You can always purchase a USB hub or a far better set of speakers separately.
