Video card and LCD displays

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GuessWho

I have a 19" Sony CRT and a nVidia MX series video board on this machine. According to my Control Panel/Display, I can get 1600 x 1200 resolution.

I've been thinking of getting a bigger LCD monitor but according to the nVidia site:

Integrated Dual-Channel TMDS

Transmitters - enabling two independent

Digital Flat Panels (DFP) displays at

resolutions up to 1280x1024.

The site also indicates different supported resolutions for CRT and LCD monitors.

Does this mean that I need a different video card if I want to use the greater resolution of the 20" or greater LCD monitors?

For routine computer work i.e. email and other web viewing, image editing, TV/DVD viewing, office related tasks but no gaming, is a 4:3 or 16:9 display preferred?

TIA,

Wayne
 
I have a 19" Sony CRT and a nVidia MX series video board on this machine.
According to my Control Panel/Display, I can get 1600 x 1200 resolution.

I've been thinking of getting a bigger LCD monitor but according to the
nVidia site:

Integrated Dual-Channel TMDS

Transmitters - enabling two independent

Digital Flat Panels (DFP) displays at

resolutions up to 1280x1024.

The site also indicates different supported resolutions for CRT and LCD
monitors.

Does this mean that I need a different video card if I want to use the
greater resolution of the 20" or greater LCD monitors?

For routine computer work i.e. email and other web viewing, image editing,
TV/DVD viewing, office related tasks but no gaming, is a 4:3 or 16:9 display
preferred?

TIA,

Wayne


(my reply)

No, what the documentation is saying is that if you hook TWO LCDs up to the
video card, each can run at up to 1280 X 1024. Unless you buy an extremely
large LCD, it shouldn't go past 1600 X 1200 native resolution, and you
already know that is supported by your current video card.

4:3 display mode is a must. 16:9 would only be good for someone who intends
to do nothing but watch DVD movies constantly. But those same movies will
look fine on a 4:3 monitor. The reason you want the 4:3 monitor is viewable
area. A 20" 16:9 monitor has significantly less viewable area than the more
square-shaped 4:3 monitor at the same diagonal size of 20". It's easy to
see why if you look at the two side by side. The 16:9 is wider, but much
shorter, so it is a squashed rectangle with not much viewable area.
Essentially, if you buy the 16:9 monitor, you are buying a much smaller
monitor. Smaller, but wider.

Or to look at it another way, you can buy a 20" 4:3 monitor, or the same
size in 16:9 would be about 26" or so. And either one would work fine, if
you can afford it. -Dave
 
"GuessWho" said:
I have a 19" Sony CRT and a nVidia MX series video board on this =
machine. According to my Control Panel/Display, I can get 1600 x 1200 =
resolution.

I've been thinking of getting a bigger LCD monitor but according to the =
nVidia site:

Integrated Dual-Channel TMDS

Transmitters - enabling two independent

Digital Flat Panels (DFP) displays at

resolutions up to 1280x1024.

The site also indicates different supported resolutions for CRT and LCD =
monitors.

Does this mean that I need a different video card if I want to use the =
greater resolution of the 20" or greater LCD monitors?

For routine computer work i.e. email and other web viewing, image =
editing, TV/DVD viewing, office related tasks but no gaming, is a 4:3 or =
16:9 display preferred?

TIA,

Wayne
Click to expand...

According to this page, a single DVI link has a capacity to handle
2.6 megapixels (H x V) at a refresh rate of 60Hz.

http://www.tech-faq.com/dvi.shtml

This page gives a formula for the necessary pixel clock rate, and
they include a 5% and 10% factors for blanking period. Blanking
period is essential for a CRT, as the beam has to retrace back to the
top and left of the screen during vertical and horizontal retrace.
An LCD doesn't have retrace, being all digital, so the blanking
intervals (periods of inactivity) can be reduced.

http://www.ecinemasys.com/technotes/files/AN010 - DVI Interconnect Limitations.pdf

The spec calls for operation at 165MHz for the pixel clock. Some
early GPUs weren't compliant with the spec, and those cards cannot
give a good quality output when running that fast.

When a lower resolution is listed, it can mean one of two things.
It can imply a high refresh rate. If the spec says 1280x1024 and
the manufacturer assumes 85Hz or 100Hz refresh rate, then that burns
up some of the link capacity. If the link is only good for 135MHz
pixel clock and not the full 165MHz, that would be another reason.

The analog output is the other output type on your video card.
The analog VGA output is constrained by the DAC used in the GPU. The
standard number these days is 400MHz, which apparently is good
for 2048x1536 @ 85Hz. I don't have a formula handy for converting
between the two sets of numbers. At high resolutions, on the
analog outputs, the problem would be cable quality - reflections
from poorly matched/terminated cables, is what messes up the
appearance of analog output.

I looked at monitors up to 23" on Newegg, and 1920 x 1200 @ 56 - 85Hz
is their resolution. That should be in range of a modern video card
with a single-link DVI connector (and perhaps reduced blanking
interval). But if the digital output on your current video card
is not good enough to make it to 165MHz, you might want to
test and see how it goes. If you see snow on the screen or other
artifacts from the digital output of your MX series card, you
should be able to pick up another cheap low end card which has
a better quality DVI output. There are still AGP cards around.

Paul
 
Paul said:
According to this page, a single DVI link has a capacity to handle
2.6 megapixels (H x V) at a refresh rate of 60Hz.

http://www.tech-faq.com/dvi.shtml

This page gives a formula for the necessary pixel clock rate, and
they include a 5% and 10% factors for blanking period. Blanking
period is essential for a CRT, as the beam has to retrace back to the
top and left of the screen during vertical and horizontal retrace.
An LCD doesn't have retrace, being all digital, so the blanking
intervals (periods of inactivity) can be reduced.

http://www.ecinemasys.com/technotes/files/AN010 - DVI Interconnect Limitations.pdf

The spec calls for operation at 165MHz for the pixel clock. Some
early GPUs weren't compliant with the spec, and those cards cannot
give a good quality output when running that fast.

When a lower resolution is listed, it can mean one of two things.
It can imply a high refresh rate. If the spec says 1280x1024 and
the manufacturer assumes 85Hz or 100Hz refresh rate, then that burns
up some of the link capacity. If the link is only good for 135MHz
pixel clock and not the full 165MHz, that would be another reason.

The analog output is the other output type on your video card.
The analog VGA output is constrained by the DAC used in the GPU. The
standard number these days is 400MHz, which apparently is good
for 2048x1536 @ 85Hz. I don't have a formula handy for converting
between the two sets of numbers. At high resolutions, on the
analog outputs, the problem would be cable quality - reflections
from poorly matched/terminated cables, is what messes up the
appearance of analog output.

I looked at monitors up to 23" on Newegg, and 1920 x 1200 @ 56 - 85Hz
is their resolution. That should be in range of a modern video card
with a single-link DVI connector (and perhaps reduced blanking
interval). But if the digital output on your current video card
is not good enough to make it to 165MHz, you might want to
test and see how it goes. If you see snow on the screen or other
artifacts from the digital output of your MX series card, you
should be able to pick up another cheap low end card which has
a better quality DVI output. There are still AGP cards around.

Paul
Click to expand...

Thanx Mike and Paul

Although I don't understand the info in the links provided by Paul, you both
seem to be saying the same thing. Namely that my current video card will
support 1600 x 1200 LCD panels over DVI.

Paul, I have considered a higher end video card, but I'm not sure if I want
to stick with my current 939 AGP mobo.

Wayne
 
"GuessWho" said:
Thanx Mike and Paul

Although I don't understand the info in the links provided by Paul, you both
seem to be saying the same thing. Namely that my current video card will
support 1600 x 1200 LCD panels over DVI.

Paul, I have considered a higher end video card, but I'm not sure if I want
to stick with my current 939 AGP mobo.

Wayne
Click to expand...

I was reading a thread on the use of Nvidia cards on the Linux
OS, and one version of the Nvidia driver was limiting the
DVI pixel clock rate artificially. The explanation was, that
the limit chosen, represented what Nvidia thought the DVI
output rate was good for. Of course, people had been running
the cards, with the DVI link running faster than the limit
that Nvidia imposed. And that is where I get the idea that
older video cards may not be able to make 165MHz on DVI.

So the DVI spec limit of 165MHz, basically has room for the
1920 x 1200 resolution at close to 60Hz refresh rate. If
the link cannot be run at 165MHz, because the video card
output just isn't good enough, then you may end up at the
next resolution down.

In terms of your interface choice, more pixels does put more
of a load on things. But since review sites seldom do 2D
benchmarking any more, it is hard for me to guess how much
of an impact your high pixel count display is going to have
on screen refreshes.

Paul
 
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