How to find HorizSync / VertRefresh rates?

Victor Engmark victor.engmark at gmail.com
Wed May 2 09:05:55 UTC 2007


On 5/2/07, Ted Mittelstaedt <tedm at toybox.placo.com> wrote:
>
> I feel the need to remind folks that the concept of refresh rates is
> completely meaningless with LCD panels.  Flatpanels do not have a single
> scan gun that draws lines at a specific time and rate of speed across a
> phosphor.


Well, the rates are both related to the video card, not the display. I'm not
sure how the card feeds the image to an LCD display, but I guess that would
depend on the enforced horizontal sync and vertical refresh rates. In any
case, it's useful to have these rates if I should ever have the need to
attach the card to an external CRT display.

The computer in the LCD panel takes the video input at a range of refresh
> rates, and converts it to a bitmapped image that is fed to the display
> crystals.  You can use whatever horizontal and vertical refresh rates
> you want, as long as they are in the table that the LCD panel's computer
> can decode, the resulting output is the same.


Even though LCD displays don't flicker, it's useful to set the refresh as
high as the panel is able to display, to get smooth transitions.

I also will remind people that the pixel counts as resolution on flatpanels
> also have no meaning.  A flat panel has a fixed natural resolution.  Any
> other resolution that you feed to it is either dithered up or dithered
> down to match the actual resolution by the display computer in the flat
> panel.
>

I'm well aware of that, but I would still like my video card and screen to
perform to the best of their abilities, in order to display the biggest
amount of data per second possible, without frying. Anything else is a waste
of resources.

-- 
Victor Engmark
Quidquid latine dictum sit, altum videtur - What is said in Latin, sounds
profound


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