comparing TFT LCD flat monitors, which one is better 850:1 or 500:1, and what do they actually mean? thanks

Those look like contrast ratios. You didn't bother to say. If so, I'd want the higher contrast. But that's me. ===================================== If at first you don't succeed, you're about average. M2

On a monitor, contrast ratio is the measure of the difference of brightness levels between the brightest white images and the darkest black images that can be reproduced. In otherwords, starting at the white level, the contrast ratio describes best how dark of a black the monitor is able to produce, consequently the higher the contrast ratio the more attractive it is to a buyer.

Generally you want a high contrast ratio & a low response time...the response time is especially important if you're a gamer. Too high a response time will result in "ghosting"