Key to buying an LCD is that unlike a CRT, you gotta spend huge piles of cash to get a good monitor. For $200 you can get a very nice 19" CRT, for $300 you get a piece of crap (and a small 15" one at that) LCD.
Dont even think about getting an LCD for less than $899 for gaming. You need to look several things for an LCD that arnt an issue on a CRT.
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The typical LCD isnt as bright as a CRT, look for a high number here, 250+ for a good LCD.
Like brightness, this is an important distinction from CRT, look for higher ratios 500:1 is nice. This mesurement has its detractors as there is no "standard" to messure this specification. But it is important, as a low contrast ratio means blacks are gray, and whites are light gray. This is one of those reasons you dont buy a monitor mail order (or you at least look at it in person THEN mail order it)
This is CRITICAL for gaming, and movie watching. Even the cheapest CRT has a response time of 10-12ms, while the BEST LCD is in the 25ms range. Also the LCD may have 2 respose times listed, a rise (turn on...usually pretty fast 10-15ms) and the fall (turn off...usually much longer 30-40ms). Many manufacturers list just the "respose time", LOWER is better, and be very very VERY cautious of any manufacturer that doesnt list this on the box...RUN AWAY!
Less critical, since most of us sit right in front, but can be annoying, especially if you are doing work around the room, and cant see the picture clearly from some parts.
Unlike the CRT, the LCD has one main resolution, any others are interpolations of that resolution. Lower resolutions tend to look blocky/blurry as the monitor trys to adapt, and higher resolutions are out. This becomes very important when you realize you may not be able to use a lower resolution (cause it looks ugly) to increase your games FPS.
With LCD displays, you can lose a single pixel...it either turns off, and stays black, or (worse) wont turn off and stays whatever color (this is BAD BAD BAD...trust me). Some manufacturers warranties will not cover ONE pixel defects (AKA only one pixel is FUBAR), I cannot speek to the number or if this is even still an issue, but I have a co-worker whos warenty would not cover a 2 month old monitor with a single pixel. Major manufactorors proably dont play this game, but what out for mr no-name LCD.
There are other considerations, but these are the big LCD only issues.
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