Fighting flicker

Tip Some people can't stand screen flicker, no way, no how, especially under certain kinds of fluorescent lights. If screen flicker really bugs you, get a flatscreen LCD monitor. They don't flicker.

A standard CRT monitor's refresh rate is the number of times per second that it redraws the image on its screen. The refresh rate is measured in Hertz, abbreviated Hz, just like the frequency of a radio wave. At a refresh rate of 70 Hz, your monitor redraws the image 70 times per second.

No matter what kind of monitor you're considering, you have to ask yourself: Does anything about the monitor bother you, such as a shiny screen that casts reflections into your eyes? If you have niggling doubts now, they'll turn into major headaches (literally and figuratively) after you've spent a thousand or two hours in front of the beast.

If a CRT monitor's refresh rate is too low, the image flickers. Most people cease to notice flicker at about 72 Hz, but this can be influenced by the monitor's CRT (cathode ray tube, or picture tube), the ambient lighting, and the sensitivity of your eyes. A refresh rate of 75 Hz looks flicker-free to almost everybody, and higher rates generally give no advantage.

A standard CRT monitor's refresh rate is variable, just as its resolution is. The maximum refresh rate typically is lower at higher resolutions: You can run 80 Hz refresh at 1024 x 768 resolution, say, but only 72 Hz at 1280 x 1024. Before you buy a monitor, try it out at its highest resolution and see if the refresh rate is high enough to eliminate flicker. Be wary of really cheap monitors, which may have a maximum refresh rate as low as 60 Hz at their highest resolution.

Flat-panel refresh rates are often measured in milliseconds - a 30 ms refresh rate is pretty standard for an LCD screen. If you play games or watch movies (or other detailed animation) on your computer, though, you may want a faster screen: 16 ms seems to represent a decent compromise between price and blurs. But be aware of the fact that, with a flat-panel monitor, a goodquality picture and DVI connection are at least as important as fast refresh numbers, even for folks who have permanent joystick implants.

Remember Resolution and refresh rate are both controlled by your computer's video adapter: Your monitor may be capable of 1280 x 1024 at 80 Hz, but your video adapter has to be able to pump out a signal at that rate. The monitor's specifications determine whether the monitor can display the image that the video adapter produces. Thus, if you upgrade your monitor, you may have to upgrade your video adapter to take advantage of your new monitor's capabilities.