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Nolan MasonFlag for United States of America

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Seeking a formula that will calculate a monitor's maximum refresh rate for a given resolution

I am looking for an affordable, black 19" monitor that supports a resolution of 1600x1200 @ 100Hz, but most online stores do not specify a monitor's maximum refresh rate for each resolution.  Can anybody tell me how to calculate the maximum resolution/refresh rate of a monitor based on its specs?  Alternatively, an acceptable answer would be to simply suggest an affordable monitor that fits this description (refurbished is fine).  I did find a formula under the "FAQ" link at the following URL, but it does not seem to be accurate:

http://www.azatek.com/service.asp#

I used it to calculate the max refresh rate on my Samsung 700NF (maximum HS of 96KHz) for 1024x768.  It worked out to 89Hz, but I've been running it at 1024x768 @ 100Hz for about a year and a half.

Any help would be much appreciated.  It's late and I'm not that sharp at the moment, so if I've left out any useful information, please let me know and I'll respond in a timely manner.  Thanks!

Nolan
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brandinius

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Ozamandis

am i missing something here? - surely its maximum refresh rate is a spec? how can u calculate it from other data - surely if you get enough data to calculate it (possible?) then you would get the max rr itself.
Hi sloopeth,
> am i missing something here? - surely its maximum refresh rate is a
> spec? how can u calculate it from other data - surely if you get enough
> data to calculate it (possible?) then you would get the max rr itself.

Well, it is certainly possible to calculate possible refresh rates, at least for CRT type monitors.
This is because there is an implied data structure in their construction and any data sent to the CRT must conform to that structure if you want it to be viewable as information.

OTOH you are right -- refresh rate is a design spec.
Just because you can calculate a legal number from the general data structure this does not mean that a particular monitor can respond to it. Choosing a refresh rate that the monitor was not designed to handle will produce a warped twisted display or even destroy it.

For LCD or TFT monitors refresh rate is actually a meaningless term except for the fact that most have a built in translator for the old structure.

Not sure of the point of this question. Why the requirement of 100Hz?
I may be wrong, but I was under the impression that ALL of the specs of a monitor are results of design goals and not dependent on each other.  For example, achieving a refresh rate of 100Hz is not so much dependent on what resolution the monitor can drive as it is the quality of the circuitry design and engineering.  A good quality 19" monitor with fast, stable circuitry will be able to run 100Hz not because of the tube size or because it can drive an XGA output res, but because it has fast, stable circuitry.  The fast that it can drive XGA is also an achievement of design goals.

Like I said, I may be wrong - but I'm sure that the refresh rate capability has nothing to do with the resolution other than if the circuitry has limited processing power available to divide between a high refresh rate, resolution and colour depth, then increasing the resolution will force the circuitry to lower something else.  Does that make sense?
>not because of the tube size

Tube size is not a factor. The exact same circuitry drives a 5" tube as a 30 " tube. Only one power supply needs to bigger for the bigger tube, assuming a constant defletion angle.

>the refresh rate capability has nothing to do with the resolution

You are only half right.

In a resolution like 1024x768
The 1024 part primarily determines the quality necessary for the video circuitry and actually has little to do with refresh speeds.
However, the 768 part determines the sweep requirments of which refresh rate is a prime factor.

Monitors need to be tuned (much like a musical instrument) for each refresh rate that they can handle. Extra components are included to support this tuning. If the design dosn't have the necessary components it will not work properly.