It also could be the resolution, older monitors usually have a lower resolution (bigger dots, less of them).

What are the differences between the new monitor and the old?

Ie. screen size, dot pitch, resolution, brightness. or better yet if you have the manufacturer model numbers we can see the published differences.

This is a start.

Do all the new monitors have the same effect?

please advise.

Current monitor w/ no problem-
Model No. D1528-LS,(13.75VS);;100-240V-1.6A;;50-60HZ

One of newer monitors-
M782;;100-240V;;60-150HZ;;1.4A.

Here's what I found;
The new monitor is a flat screen crt, 17".
The old one was 15" stadard (curved) screen.

The refresh rate on the old one is slower in all modes. This would mean that the screen would likely show more flicker on the old screen, that is unless the phosphor is slower (which is likely the case) in that case, the newer unit would show more "flash" as the beam is scanned from dark to light areas.

Typically, it is the screen flicker that bothers people. Since the older one is better, aside from intangible items like xray emmission, ozone emmission, and magnetic fields, I would think that the most likely problem is with the phosphour and flash effect. In general the larger screen will have higher emmisions but the difference in size is so small that I don't consider this significant. All the montiors emmisions must be certified to a international standard and while one unit may slip through with excessive emmisions, it is not likely that a number of different units would all have this problem.

What to do.

The easiest on the eyes is definately an LCD. These are the real slim units that are about 2" thick. Unfortunately a good one costs more than a comparable sized tube. Since you are using 15" now, maybe go with a 15" LCD, which is only a little more money than a good 17" tube. One advantage is that the LCD screen image is slower so that there is virtually no flicker. The screen also does not have focus or convergence problems like the tube.

Alternatively, you might want to try to adjust the refresh, contrast and brightness one of the new monitors to try to simulatre the older one. You can do this with the windows control panel settings.

My experience with this shows that you can pick some settings that are entirely incompatable with long hours in front of the screen, it is however a very personal setting (I cannot see the flicker that drives other people to almost throw up!)

In general, the lower you can run the intensity, the better, this since the "flash" becomes quite noticable at the high intensities. As the monitors get old, the intensity decreases significantly and this may be part of the difference you are seeing.

Again, I think that the LCD would be your best bet. If you do get one, just make sure the screen goes dark when you are not using it as the backlight has a limited life span of 10 to 20k hours (about 1 to 2 years)(do this with the right click on the desk top and set the power savng mode to tyurn off the screen).

You might want to check out www.cnet.com for LCD monitors and you can get an idea of what they cost. Dell also has them as an add on to the basic system so you can use that as a reference price.