Introduction
Purchasing a monitor is no longer a simple decision, with the market awash with offerings from major manufacturers. Add to this the extra complication of whether to opt for a CRT or LCD based monitor, the decision-making process turns into a nightmare.
CRT (cathode ray tube) monitors have been with us for a long time and continue to serve us well, as of late prices of 19" monitors have dropped to around £345.00 ex VAT, this compared to 18 months ago when they were £600 plus. However, the monitors that will be the envy of your colleagues at work require hardly any space as they are incredibly thin and very high tech looking are not CRT based but Liquid Crystal Display (LCD) technology. Aside from the cost of these monitors, we could not come up with any reasonable reason as to why you would want to continue to use monitors based on CRT technology.

LCD panels differ from CRT in the way image is presented to us on the screen. LCD panels have a fixed number of liquid crystal cells and display only one resolution at full-screen size. There are no convergence problems with LCD panels, because each cell is switched on and off individually, as opposed to CRT screens, which rely on convergence from electron guns for clarity. LCD panel to not suffer from flicker or resolution problems like their counterparts, a panel set as 60Hz will be as steady as one set at 75Hz as the LCD cells are either on or off. This is why when you first feast your eyes on an LCD panel the sharpness of the image and text will take your breath away, and send buying signals to the salesman standing next to you.

All is not perfect with LCD panel technology, as a rule of thumb on a 1024 x 768 monitor, there are three cells (red, green and blue) for each pixel which would amount to 2,359,296 cells. Is there a chance all of these cells may be perfect? Highly unlikely, as some will be stuck on ("bright" cells) or off ("dark" cells). This will be dependent on your eyesight, as no salesman will be able to advise you. The flaws have occurred because each panel has to complete the production cycle before any flaws can be highlighted, one of the reasons why LCD active-matrix panels are expensive to buy. The LCD panels are lit by fluorescent tubes that line the back of the unit, and occasionally you'll see ghosting or streaking where a large image will have a different colour shade at opposite ends, notice brighter lines in some parts of the screen than others. Those readers who have or own a notebook will know exactly what we mean.

15" LCD monitors have tumbled in price as of late, and with the viewable image area almost equating to some 17" CRT monitors, we decided to review 15" entry-level LCD monitors from 4 leading manufacturers. We were rather disappointed to receive a monitor from a well know manufacturer which did not work at all, due to the pressure of tight deadlines, we were not in a position to allow the manufacturer a second bite of the cherry. So we were left with 3 leading manufacturers, with the lab guys wanting to get their hands on them to test. Some of us were going to be disappointed, not me though l got to review them!

How we carried out our test
Our testing was based with business users in mind, and with emphasis on Set-up and ease of use. The testing was done using Displaymate (www.displaymate.com), which has the ability to generate hundreds of test patterns designed to highlight any flaws in monitors. The resolution we tested under was 1024 x 768 at 16bit colour depth and 72Hz vertical refresh rate. Rather than having a definite result at the end of the testing, each pass or failure is more susceptible to the opinion (or eyesight!) of the person actually doing the review. We tried to achieve some consistency by getting opinions from three different people for each test so it wasn't just down to one individual.

TEST SYSTEM:
CPU: Intel Pentium III - 550Mhz - 512k - 100FSB
Motherboard: Abit BE6-II - BX Chipset
Memory: 64Mb SDRAM PC100 - 7ns
HDD: Quantum Fireball LCT10 - 20.4GB UDMA66 5400rpm
FDD: 3.5" 1.44Mb - Panasonic
CD ROM: 48 x Creative
Video Card: Diamond Viper 770 AGP 16Mb
Sound Card: Creative PCI128
Modem: Diamond Internal 56i SST Soft Modem
Keyboard: Keytronic
Mouse: Ms Mouse Defender - 2 button

Setup
This part of the test determines the fine image sharpness, colour scales to ensure sharp reproduction on the monitor, black and white levels are set correctly, testing for glare and specular (mirror-like) reflections, brightness and contrast controls are set correctly, and checks the colour level intensity.

Geometry & Distortion
The test checks to see whether the brightness and contrast controls are set correctly, and determines the monitor's black-level and white level.

Sharpness & Resolution
This uses finer detailed images to check the monitor's capabilities in showing more definition by displaying very fine horizontal and vertical lines on the screen.