LCD digital monitor behaviour

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When using a DVI connection from the video card to the LCD monitor, does
it ensure exact 1:1 pixel displays, or does it expand the image, if the
video card's current geometry is less than what the monitor's native
resolution is? For example, if I have a 1680x1050 LCD monitor and the
video card is set up for 1280x1024, will it display the 1280x1024 as a
smaller box or will it stretch to fill out the whole screen.

I know with analog, stretching seems to be the default. But I am seeking
the "perfect pixel" display and currently can only output 1280x1024. There
are some monitors that do 1280x1024, but I'd rather have a larger monitor
if it will for now do the 1280x1024 as a smaller box and keep perfect pixel
displaying.

Maybe this is an option on some monitors. But I have looked at hundreds
online and none specify any aspect of this at all. And I am sure stores
would not have anyone working there with enough clue to hook up a computer
outputting 1280x1024 digitally to a wide minitor like 1680x1050.
 
When using a DVI connection from the video card to the LCD monitor, does
it ensure exact 1:1 pixel displays, or does it expand the image, if the
video card's current geometry is less than what the monitor's native
resolution is? For example, if I have a 1680x1050 LCD monitor and the
video card is set up for 1280x1024, will it display the 1280x1024 as a
smaller box or will it stretch to fill out the whole screen.

I know with analog, stretching seems to be the default. But I am seeking
the "perfect pixel" display and currently can only output 1280x1024. There
are some monitors that do 1280x1024, but I'd rather have a larger monitor
if it will for now do the 1280x1024 as a smaller box and keep perfect pixel
displaying.

Maybe this is an option on some monitors. But I have looked at hundreds
online and none specify any aspect of this at all. And I am sure stores
would not have anyone working there with enough clue to hook up a computer
outputting 1280x1024 digitally to a wide minitor like 1680x1050.
Click to expand...

AFAIK, the design intent of an LCD computer monitor, is to emulate the
behavior of a CRT computer monitor. It'll stretch to fill.

You can get 17" and 19" LCD monitors at 1280x1024. There are some 20" and
21" non-wide-screens at 1600x1200, but the price climbs rapidly. I'm not
sure a widescreen would make very good use of your 1280 limit, if that
is the limit.

You can get video cards with a PCI connector, for a desktop. This one is
a low profile, dual slot, PCI card, with two DVI-I connectors. I have no
idea if you can get a regular sized PCI faceplate for it. While you
can game on it, this would not be my first choice for Oblivion :-)

http://www.newegg.com/Product/ProductReview.aspx?Item=N82E16814161074
http://www.hisdigital.com/html/product_sp.php?id=285 (nearest similar product)
http://ati.amd.com/products/radeonx1550/specs.html

This is an example of a laptop solution, but this would not be for gaming.

http://www.villagetronic.com/vtbook/techspecs.html
http://sewelldirect.com/vtbookpcmciacard.asp $230

Also, there are some video products (may not be shipping yet), which use
Expresscard. That is the PCI Express equivalent of a PCMCIA card. The idea
is, an Expresscard plugs into the laptop and buffers and sends the PCI
Express digital connection, to a separate "box" that holds a real desktop video card.
That, in turn, drives the external monitor. It means a desktop PCI Express card,
can be run on a modern laptop, but with the limited (250MB/sec) bandwidth of a
PCI Express x1 laneway.

HTH,
Paul
 
| (e-mail address removed) wrote:
|> When using a DVI connection from the video card to the LCD monitor, does
|> it ensure exact 1:1 pixel displays, or does it expand the image, if the
|> video card's current geometry is less than what the monitor's native
|> resolution is? For example, if I have a 1680x1050 LCD monitor and the
|> video card is set up for 1280x1024, will it display the 1280x1024 as a
|> smaller box or will it stretch to fill out the whole screen.
|>
|> I know with analog, stretching seems to be the default. But I am seeking
|> the "perfect pixel" display and currently can only output 1280x1024. There
|> are some monitors that do 1280x1024, but I'd rather have a larger monitor
|> if it will for now do the 1280x1024 as a smaller box and keep perfect pixel
|> displaying.
|>
|> Maybe this is an option on some monitors. But I have looked at hundreds
|> online and none specify any aspect of this at all. And I am sure stores
|> would not have anyone working there with enough clue to hook up a computer
|> outputting 1280x1024 digitally to a wide minitor like 1680x1050.
|>
|
| AFAIK, the design intent of an LCD computer monitor, is to emulate the
| behavior of a CRT computer monitor. It'll stretch to fill.

CRTs don't stretch to fill. You can adjust it as desired. Just how
much depends on the quality of the display. The one I own is a higher
quality Sony model that has plenty of range to it.

LCDs _should_ offer the ability to display video that has geometry lower
than the display's native geometry by boxing the video in with perfect
1:1 pixel alignment. That shouldn't be the only way to do it. It should
_also_ offer expanding it to fill at least one dimension while retaing
correct aspect ratio, as well as expanding to fully fill both dimensions.
If the source video geometry is the same as the diplay, then all three of
these are the same thing.

Note, this would be for "high end" LCDs for which price is not the only
competing factor. The "low end" LCDs would be striped to barely working
so they can be offered under $150.


| You can get 17" and 19" LCD monitors at 1280x1024. There are some 20" and
| 21" non-wide-screens at 1600x1200, but the price climbs rapidly. I'm not
| sure a widescreen would make very good use of your 1280 limit, if that
| is the limit.

True, a widescreen monitor would not make good use of 1280x1024. But a
larger screen (with larger pixels) would at least let me set the display
further back from my eyes. The up close display is bad for eyes.


| You can get video cards with a PCI connector, for a desktop. This one is
| a low profile, dual slot, PCI card, with two DVI-I connectors. I have no
| idea if you can get a regular sized PCI faceplate for it. While you
| can game on it, this would not be my first choice for Oblivion :-)
|
| http://www.newegg.com/Product/ProductReview.aspx?Item=N82E16814161074
| http://www.hisdigital.com/html/product_sp.php?id=285 (nearest similar product)
| http://ati.amd.com/products/radeonx1550/specs.html

Matrox does make a video card with a dual DVI in a single slot. They also
make some low provide PCI cards with a special "double DVI" connection that
requires a special cable that breaks out to 2 DVI connectors on the other
end.


| This is an example of a laptop solution, but this would not be for gaming.
|
| http://www.villagetronic.com/vtbook/techspecs.html
| http://sewelldirect.com/vtbookpcmciacard.asp $230
|
| Also, there are some video products (may not be shipping yet), which use
| Expresscard. That is the PCI Express equivalent of a PCMCIA card. The idea
| is, an Expresscard plugs into the laptop and buffers and sends the PCI
| Express digital connection, to a separate "box" that holds a real desktop video card.
| That, in turn, drives the external monitor. It means a desktop PCI Express card,
| can be run on a modern laptop, but with the limited (250MB/sec) bandwidth of a
| PCI Express x1 laneway.

But that's better than plain old PCI bandwidth.
 
| AFAIK, the design intent of an LCD computer monitor, is to emulate the
| behavior of a CRT computer monitor. It'll stretch to fill.

CRTs don't stretch to fill. You can adjust it as desired. Just how
much depends on the quality of the display. The one I own is a higher
quality Sony model that has plenty of range to it.

LCDs _should_ offer the ability to display video that has geometry lower
than the display's native geometry by boxing the video in with perfect
1:1 pixel alignment. That shouldn't be the only way to do it. It should
_also_ offer expanding it to fill at least one dimension while retaing
correct aspect ratio, as well as expanding to fully fill both dimensions.
If the source video geometry is the same as the diplay, then all three of
these are the same thing.

Note, this would be for "high end" LCDs for which price is not the only
competing factor. The "low end" LCDs would be striped to barely working
so they can be offered under $150.
Click to expand...
[...]

Those are all functions of the video system, and the image/video player,
not of the monitor. The monitor just displays whatever information is
sent to it. If the video card is correctly set, then a 1024x768 image
will be displayed it as 1024x768, nicely centred on the 1280x768 screen.
If the image viewer/video player sends a 640x480 image, it will will be
centred in the program's window, with black space all round it if that
window is larger than 640x480. Etc.

EG, when I replaced the 17" 4:3 monitor with a 20" 16:9 monitor, the
card stretched the image to fill the available display space. I changed
that by resetting the display format in the video card's settings
utility. The display does _not_ stretch a 4:3 video source to fit the
16:9 format. It produces the black bars at each end, just as it should.

Wide screen TVs are a different issue. What they do with the signal they
receive depends on how they've been set up. In every bar and restaurant
I've been in lately, the 4:3 sources have been stretched to fit 16:9.
Looks ugly as hell - I really don't understand why people aren't pissed
off by it, especially since a couple of button pushes will make the TV
display the picture correctly. But an anecdote may explain, or at least
refocus the question: Many years ago, when I was till teaching, we were
discussing camera angles, etc. I mentioned in passing that wide screen
movies have a different effect because they can, for example, put more
space between people. One of my students was puzzled. He had never
noticed that the movies he watched at the local theatre came in
different shapes -- and he watched them all!

HTH
 
Maybe this is an option on some monitors. But I have looked at hundreds
online and none specify any aspect of this at all. And I am sure stores
would not have anyone working there with enough clue to hook up a computer
outputting 1280x1024 digitally to a wide minitor like 1680x1050.
Click to expand...

Most monitors have an option -- I haven't encountered one yet that
doesn't have that option, but I've only gone out of my way to check all
the ones I own here (Acer, Dell, HP, and a white-label generic)
 
In message <[email protected]> Wolf
Kirchmeir said:
Those are all functions of the video system, and the image/video player,
not of the monitor. The monitor just displays whatever information is
sent to it. If the video card is correctly set, then a 1024x768 image
will be displayed it as 1024x768, nicely centred on the 1280x768 screen.
If the image viewer/video player sends a 640x480 image, it will will be
centred in the program's window, with black space all round it if that
window is larger than 640x480. Etc.
Click to expand...

*sigh*

Unless the computer itself only outputs a smaller image then the
monitor's upper resolution. It can be a function of software, but it's
pretty obvious that the poster is asking about hardware capabilities.
 
| Those are all functions of the video system, and the image/video player,
| not of the monitor. The monitor just displays whatever information is
| sent to it. If the video card is correctly set, then a 1024x768 image
| will be displayed it as 1024x768, nicely centred on the 1280x768 screen.
| If the image viewer/video player sends a 640x480 image, it will will be
| centred in the program's window, with black space all round it if that
| window is larger than 640x480. Etc.

Maybe in your dreams. I've seen severe lack of centering on both CRT and
LCD, for the automatic handling of a new video mode. In some cases there
isn't even enough adjustment range in the monitor to correct it. And this
is in addition to other display errors such as too wide or to narrow or
too short or too tall.


| EG, when I replaced the 17" 4:3 monitor with a 20" 16:9 monitor, the
| card stretched the image to fill the available display space. I changed
| that by resetting the display format in the video card's settings
| utility. The display does _not_ stretch a 4:3 video source to fit the
| 16:9 format. It produces the black bars at each end, just as it should.

This can be done at either end. It isn't always done. In some cases
the video driver can determine the monitor and change the geometry to
match that of a native LCD.


| Wide screen TVs are a different issue. What they do with the signal they
| receive depends on how they've been set up. In every bar and restaurant
| I've been in lately, the 4:3 sources have been stretched to fit 16:9.
| Looks ugly as hell - I really don't understand why people aren't pissed
| off by it, especially since a couple of button pushes will make the TV
| display the picture correctly. But an anecdote may explain, or at least
| refocus the question: Many years ago, when I was till teaching, we were
| discussing camera angles, etc. I mentioned in passing that wide screen
| movies have a different effect because they can, for example, put more
| space between people. One of my students was puzzled. He had never
| noticed that the movies he watched at the local theatre came in
| different shapes -- and he watched them all!

There are people around who believe that because the screen is widescreen
that they are required to stretch the picture. That's what it's for in
their mind.
 
| Those are all functions of the video system, and the image/video player,
| not of the monitor. The monitor just displays whatever information is
| sent to it. If the video card is correctly set, then a 1024x768 image
| will be displayed it as 1024x768, nicely centred on the 1280x768 screen.
| If the image viewer/video player sends a 640x480 image, it will will be
| centred in the program's window, with black space all round it if that
| window is larger than 640x480. Etc.

Maybe in your dreams. I've seen severe lack of centering on both CRT and
LCD, for the automatic handling of a new video mode. In some cases there
isn't even enough adjustment range in the monitor to correct it. And this
is in addition to other display errors such as too wide or to narrow or
too short or too tall.
Click to expand...

OK, I see your point. I've never had that problem, probably because I've
never messed around with that many video modes. OTOH, as detailed in the
rest of my post, I did have a problem when i switched monitors, and had
to change the video card's settings.

[...]
| Wide screen TVs are a different issue. What they do with the signal they
| receive depends on how they've been set up. In every bar and restaurant
| I've been in lately, the 4:3 sources have been stretched to fit 16:9.
| Looks ugly as hell - I really don't understand why people aren't pissed
| off by it, especially since a couple of button pushes will make the TV
| display the picture correctly. But an anecdote may explain, or at least
| refocus the question: Many years ago, when I was till teaching, we were
| discussing camera angles, etc. I mentioned in passing that wide screen
| movies have a different effect because they can, for example, put more
| space between people. One of my students was puzzled. He had never
| noticed that the movies he watched at the local theatre came in
| different shapes -- and he watched them all!

There are people around who believe that because the screen is widescreen
that they are required to stretch the picture. That's what it's for in
their mind.
Click to expand...

Yup, and they have no sense of proportion. Probably went to a school
that cut arts classes, because they are, after, all "mere frills." Bah!
 
| (e-mail address removed) wrote:
|>
|> | Those are all functions of the video system, and the image/video player,
|> | not of the monitor. The monitor just displays whatever information is
|> | sent to it. If the video card is correctly set, then a 1024x768 image
|> | will be displayed it as 1024x768, nicely centred on the 1280x768 screen.
|> | If the image viewer/video player sends a 640x480 image, it will will be
|> | centred in the program's window, with black space all round it if that
|> | window is larger than 640x480. Etc.
|>
|> Maybe in your dreams. I've seen severe lack of centering on both CRT and
|> LCD, for the automatic handling of a new video mode. In some cases there
|> isn't even enough adjustment range in the monitor to correct it. And this
|> is in addition to other display errors such as too wide or to narrow or
|> too short or too tall.
|
| OK, I see your point. I've never had that problem, probably because I've
| never messed around with that many video modes. OTOH, as detailed in the
| rest of my post, I did have a problem when i switched monitors, and had
| to change the video card's settings.

A well designed video detection circuit plus properly written software could
easily handle any video mode given to it. It could center it based on an
estimate between the sync pulses of there no actual video at that time, or
detect the begin and end edges of actual video. Any combination of vertical
and horizontal frequencies over a very wide range could be handled. Vertical
is a bit more complicated in LCD due to the way it has to be converted. But
it is at least detectable. LCD inherintly has "conversion" so it can handle
a much wider range than CRT without a converter ever could.
 
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