How to pick an LCD Monitor
by Alereon
Understanding LCD Monitor specifications
Response Time: The response time of an LCD monitor is, in short, how long it takes for a pixel to change colors to display a new image. Response times are listed in milliseconds (ms), and determine whether ghosting, which appears as a blurry trail behind moving objects, is visible. Response times are sometimes listed with two numbers, rising and falling, which should be added together to find the true response time. A response time of 25ms is adequate for general use but probably not gaming, a response time of 16ms is adequate for fast-paced gaming, and a response time of 12ms or lower means ghosting should never be visible, even in games with the fastest motion.
Contrast Ratio: The contrast ratio of an LCD monitor is the ratio of the brightest white the monitor can produce to the darkest black the monitor can produce. Higher contrast ratios make for a more vivid picture. A contrast ratio of 400:1 or higher is good.
Brightness: The brightness of an LCD monitor is, simply enough, how bright the image is. Brightness is measured in candelas per square meter, or cd/m2. 250cd/m2 or higher brightness is more than adequate for most situations.
Resolution: How many pixels wide and tall the panel is. Unlike CRT monitors, LCDs run at a single fixed resolution; attempting to use the monitor at other than its native resolution results in a blurry image or black bars. 15" LCDs are 1024x768, 17", 18", and 19" LCDs are 1280x1024, and 20" and larger LCDs are 1600x1200. Note that 17", 18", and 19" LCDs all have the same resolution, thus they have the exact same amount of useable screen space. 18" and 19" LCDs are just zoomed in a bit compared to 17" LCDs, a fact which for many does not justify their substantially higher price. 17", 18", and 19" LCDs are also a different shape than most CRTs; they're slightly taller, meaning that an image that displays perfectly on a standard CRT monitor will either be stretched or have black bars on the top and bottom when displayed on a 17", 18", or 19" LCD. Resolutions for widescreen LCDs vary, but are commonly 1600x1080 or 1920x1200. Resolutions for laptop LCDs do not follow such strict size standards and vary widely.
Interface: How the LCD monitor receives its video signal. As LCDs are a digital display technology, it's best to give them a digital signal to work with.
DVI, or Digital Video Interface, is the connection that carries a digital signal from a videocard to an LCD monitor. Nearly all videocards have a DVI port, which is normally white and has a + shape on the left side.
VGA (Also called D-SUB, Analog RGB, and HD-15) is the standard interface is the standard for CRT monitors.
Svideo, Composite, and Component are analog interfaces commonly used to carry TV signals.
HDMI, High Definition Multimedia Interface, is a new digital interface that's found primarily on HDTVs.
Not using a digital interface such as DVI will nullify many of the image quality advantages LCDs have over CRT monitors, though the quality difference depends on the monitor's signal acquisition circuitry as well as the quality of the signal coming out of the computer. Most very cheap LCD monitors only support a VGA interface, and I strongly recommend purchasing a monitor that has DVI input, even if your current videocard does not support it. Note that if you're planning on using your LCD monitor as an HDTV, you may need to buy a monitor that supports HDCP, or High Definition Copy Protection. Otherwise your HDTV receiver may stop transmitting a video signal after several seconds, displaying an authentication error.
Viewing Angle: How far off-center you can view the screen from and still see an image. LCD monitors, unlike CRTs, have problems with brightness and color accuracy if you're not looking directly at the display. These days, LCD monitors offer viewing angles of 120 degrees or more.
Example of an LCD Monitor with good specifications
An example of a good LCD monitor would be one that is 17", has a response time of 16ms or less, has DVI and VGA inputs, has a contrast ratio of 400:1 or more, has a brightness of 250cd/m2 or more, and a viewing angle of 120 degrees or more. Any LCD monitor that meets these specifications should perform very well for any given task, including high-speed gaming. An LCD monitor with these specifications should be available for under $250, possibly under $200 including rebates. More expensive monitors generally offer better color reproduction and image quality.
LCD Monitors compared to CRT Monitors
Advantages of LCD Monitors: LCD monitors are smaller, lighter, use less power, have a sharper picture and higher resolution, are not susceptible to interference, have no flicker, and have perfect screen geometry and no distortion.
Advantages of CRT Monitors: CRT monitors are cheaper, more flexible in terms of display resolutions, can display higher refresh rates, can be brighter, can have better contrast, and can have better color reproduction.
Common problems with LCD Monitors
Dead Pixels: Some LCD monitors come with dead pixels. Dead pixels come in two forms: Stuck on, and stuck off. A pixel that is stuck on is black at all times, and will appear as a tiny dot on a monitor displaying a bright image. A pixel that is stuck off is fully either Red, Green, or Blue at all times, and will appear as a tiny dot on a monitor displaying a dark image. In some cases, a dead pixel can be brought back to life by gently massaging it through a lint-free cloth for a period of minutes. Care must be taken to avoid scratching or cracking the monitor. The best way to check for dead pixels is to make the screen display solid Red, then solid Green, then Solid Blue, then solid Black. Any dots on the screen appearing during these tests (that don't wipe off) are dead pixels. Retailers and manufacturers vary on their willingness to accept returns of monitors with dead pixels, either requiring a blanket number (such as 8), a cluster (such as 4 pixels within a square inch), or considering where the dead pixels lay on the screen (with pixels at the center of the screen weighted more than those on the edge).
Backlight Defects: An LCD monitor with a backlight defect will have visibly uneven brightness over the screen. Solid Black and solid White images are the best way to check for backlight problems. In the event of a complete backlight failure, the image will appear very faint and dark, and possibly be visible only in bright light or with a flashlight shining on the monitor.
Specific monitor recommendations
All recommended monitors feature response times of 16ms or less and DVI interfaces.
17" Value: neovo M-17 17" 12ms $199.99 after MIR at
http://www.newegg.com/Product/Product.asp?Item=N82E16824163126
17" Midrange: acer AL1715s-8 Silver 17" 8ms $245 at
http://www.newegg.com/Product/Product.asp?Item=N82E16824009053
17" Quality: ViewSonic VX724 17" 4ms $315.99 at
http://www.newegg.com/Product/Product.asp?Item=N82E16824116359
19" Value: Aopen F90JS 16ms $229 after MIR at
http://www.newegg.com/Product/Product.asp?Item=N82E16824174024
19" Quality: Acer AL1914SMD-8 8ms $295.99 at
http://www.newegg.com/Product/Product.asp?Item=N82E16824009044
20" Widescreen: Dell Ultrasharp 2005FPW 8ms ~$450 after MIR at Dell Small Business (Deals vary, if it's not discounted wait a week)
20.1" Quality: Dell Ultrasharp 2001FP 16ms ~$500 after MIR at Dell Small Business (Deals vary, if it's not discounted wait a week)
24" Widescreen: Dell Ultrasharp 2405FPW 8ms ~$800 after MIR at Dell Small Business (Deals vary, if it's not discounted wait a week)
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