RGB to S-video converter for using HDTV as computer monitor?

[Mackie]

A pal of mine with low sales resistance went out and against advice,
bought a Wal-Mart special; an HP Pavilion "Slimline" with No S-video
and HDMI outputs. According to the specifications for this HP S3713W,
the video/graphics are all on the motherboard . . .

http://h10025.www1.hp.com/ewfrf/wc/...39&lc=en&dlc=en&cc=us&lang=en&product=3870526

Furthermore, though there is in her "Slimline" one available slot
provided to accept a "replacement" graphics card (for whichever model
would have such a card) according to the manual, it will accept only
"low profile" cards, and even at that they warn it still might not
fit, so as to allow the inputs and outputs be exposed at the opening.
And since for her computer, this would not be a card replacement,
those "cables" and plugs they refer to would be who-knows-where on the
motherboard, or even hard-wired to it.

So now I'm wondering about something like this RGB to S-video
converter . . .

http://www.js-technology.com/product_info.php?products_id=34

My friend is largely blind, but she can see images and text on a large
screen. My question is this: would such a converter enable video
output from her computer to a large 42" LCD HDTV--and if so, would the
mouse function be operative on that large screen same as on the 19"
LCD monitor that came with her computer? Most importantly, would she
get a full 42" display of her desktop and applications?

Sure hope somebody can help. I'd really like to be able to bring her
some good news, despite her screw-up. She got it cheap! Maybe she can
have her "BigASS TV" computer monitor and keep eating cake too?

 

[almostbob]

many lcdtv have a vga port as well as hdmi & svideo hiding somewhere, if it
does its just a connector cable from local geekstore to do the connection, &
yes you should be able to set it a full 42 inch wide, & mouse etc works

 

[Paul]

A pal of mine with low sales resistance went out and against advice,
bought a Wal-Mart special; an HP Pavilion "Slimline" with No S-video
and HDMI outputs. According to the specifications for this HP S3713W,
the video/graphics are all on the motherboard . . .

http://h10025.www1.hp.com/ewfrf/wc/...39&lc=en&dlc=en&cc=us&lang=en&product=3870526

Furthermore, though there is in her "Slimline" one available slot
provided to accept a "replacement" graphics card (for whichever model
would have such a card) according to the manual, it will accept only
"low profile" cards, and even at that they warn it still might not
fit, so as to allow the inputs and outputs be exposed at the opening.
And since for her computer, this would not be a card replacement,
those "cables" and plugs they refer to would be who-knows-where on the
motherboard, or even hard-wired to it.

So now I'm wondering about something like this RGB to S-video
converter . . .

http://www.js-technology.com/product_info.php?products_id=34

My friend is largely blind, but she can see images and text on a large
screen. My question is this: would such a converter enable video
output from her computer to a large 42" LCD HDTV--and if so, would the
mouse function be operative on that large screen same as on the 19"
LCD monitor that came with her computer? Most importantly, would she
get a full 42" display of her desktop and applications?

Sure hope somebody can help. I'd really like to be able to bring her
some good news, despite her screw-up. She got it cheap! Maybe she can
have her "BigASS TV" computer monitor and keep eating cake too?

Generally, you'd want to start with the make and model number of the
42" LCD TV, download the manual, and inspect it for connector options.
Composite or S-video might be my last choice for an interface (text
would be almost unreadable and blurry, just like text is on TV
broadcasts). Some LCD TVs have VGA connectors, in which
case your problem is solved for testing purposes. You could
try it out right away.

If there are computer related interfaces, there may be resolution
tables in the LCD TV manual as well. It is best if the computer can
be put in "native" resolution mode. If the TV was 1366 x 768 pixels,
then you'd want to find that value listed as an option in the
tables. That way, there is no re-sampling of the computer image.
That helps keep the text sharp.

So post the TV make and model first.

The other issue, is looking inside the slimline case, to get an
estimate of how long a video card it will accept. If you could find
a web link on the HP site, showing a picture of any video card
offered as an option for the computer at introduction, that
also might guide you in finding an aftermarket video card.
If you aren't gaming, the card doesn't have to be expensive.

This "low profile ready" card for $40, ships with the regular height
faceplate bolted to it. You unplug the VGA cable from the
video card, unscrew the faceplate, and then install the
low profile faceplate. Then, the video card has two connectors,
an HDMI and what is presumably a DVI-I connector. The HDMI
might go to the LCD TV. There is no auxiliary power cable for
the card, so you just insert the card in the slot, and use
whatever clamp exists at the faceplate, to hold it in place.
(Some cases use a screw-less fastener.)

http://www.newegg.com/Product/Product.aspx?Item=N82E16814125251

http://www.gigabyte-usa.com/Product...VGA&ProductID=2927&ProductName=GV-R435OC-512I

The following one is a previous generation HD 2400 Pro, with
S-video and composite, as well as a DMS-59 to dual DVI or dual VGA.
So this has a total of three connector outputs, of which you can use
any two. You could drive a VGA and a TV for example. Or two VGA.
The other card offered two of three as well.

It is possible, when the video card is plugged in, the motherboard
VGA connector will be disabled, but you probably won't need it.
The only thing I see missing from this next card, that I might regret
later, is any mention of HDCP. So if you were to use a
DVI-I to HDMI passive dongle as an adapter, then it is
possible that the missing HDCP may cause issues with
some movie playback.

http://www.newegg.com/Product/Product.aspx?Item=N82E16814129106

http://en.wikipedia.org/wiki/Hdcp

http://www.microsoft.com/whdc/device/media/output_protect.mspx

Some cards with HDMI, support audio over HDMI as well. On
an ATI card, the digital audio may be built in (and use
a RealTek HDaudio driver to get working - that can be
confusing when you see it in Device Manager). Some Nvidia
cards use an SPDIF passthru connector instead, requiring a cable
be run from the motherboard SPDIF (RCA), to a two pin connector
somewhere on the video card. Just in case you were
wondering why a video card would have a twisted pair cable
with some goofy connectors on it. That is for audio passthru
on designs that could drive HDMI, but don't have HDaudio right
on the video card itself. The workaround for this cabling
nightmare, is just to run audio from the green Line-Out on
the computer (analog audio), to a couple RCA audio jacks on the TV set,
then select the right input with the TV on-screen display. The
same as you'd have to do, if using S-video or composite signals.

The LCD TV manual should make this a lot clearer and easier
to understand. I'm throwing out lots of jargon here, to
help you find references to stuff.

Paul

 

[Just Me]

many lcdtv have a vga port as well as hdmi & svideo hiding somewhere, if it
does its just a connector cable from local geekstore to do the connection, &
yes you should be able to set it a full 42 inch wide, & mouse etc works

Ah, Great! Thanks a bunch AlmostBob.

 

[Just Me]

Wow. This is right on the money, Paul. I'll get this off to her,
pronto!
Thanks a million.

 

[John]

While we're on this subject, I have a question or two to ask.
see below

Generally, you'd want to start with the make and model number of the
42" LCD TV, download the manual, and inspect it for connector options.
Composite or S-video might be my last choice for an interface (text
would be almost unreadable and blurry, just like text is on TV
broadcasts). Some LCD TVs have VGA connectors, in which
case your problem is solved for testing purposes. You could
try it out right away.

Are you saying that VGA is the best? I've always thought that S-Video or
perhaps HDMI gives us better and sharper picture compared to VGA.

If there are computer related interfaces, there may be resolution
tables in the LCD TV manual as well. It is best if the computer can
be put in "native" resolution mode. If the TV was 1366 x 768 pixels,
then you'd want to find that value listed as an option in the
tables. That way, there is no re-sampling of the computer image.
That helps keep the text sharp.

Once again, wouldn't HDMI give us sharpest picture? You're correct about
composite. I have my obsolete PC connected to my old tube TV with a
composite cable. Text is so blurry and unreadable. I have never seen a PC
connected to (high def) TV with other types of connection (VGA, S-Video,
HDMI etc). I'm planning to buy an LCD TV and a new PC. That is why I ask.
What type of connection gives us the best picture quality? Thanks much.

 

[Paul]

While we're on this subject, I have a question or two to ask.
see below



Are you saying that VGA is the best? I've always thought that S-Video or
perhaps HDMI gives us better and sharper picture compared to VGA.


Once again, wouldn't HDMI give us sharpest picture? You're correct about
composite. I have my obsolete PC connected to my old tube TV with a
composite cable. Text is so blurry and unreadable. I have never seen a PC
connected to (high def) TV with other types of connection (VGA, S-Video,
HDMI etc). I'm planning to buy an LCD TV and a new PC. That is why I ask.
What type of connection gives us the best picture quality? Thanks much.

HDMI/DVI > VGA/Component > S-video > Composite

The HDMI/DVI is digital, and gives perfect transmission as long
as there is no resolution resampling. If the transmitted resolution
doesn't match the native resolution (the actual pixels on the screen),
the image has to be resampled. If you make the cables too long, or
use a really cheesy cable, you'll start to see "colored snow" mixed
with the picture. As long as the cabling is right, the picture will
be error free.

VGA carries analog RGB. Component video (three coax cables YPrPb)
carries analog color as well. Both have to be digitized by the LCD TV before
being displayed. The transmission can be every bit as good if there
aren't problems with cabling, connectors, or output driver on the
video card. The analog to digital conversion process at the LCD TV
makes this a slightly less preferred method (we don't know how
good that ADC is). The image may contain ghosting, for example,
if there is an impedance mismatch on the cables.

S-video and composite offer a bandwidth of around 4MHz as far as
I know. The video format is interleaved. S-video has the
advantage of separating the video signal into Y and C,
which gives a slight quality boost to a bad idea. These
two are the last options I'd want to explore, for computer
usage. The text would have to be pretty big on the screen
to be readable. You wouldn't want to do Microsoft Word
this way I tried to boot my FreeBSD machine once,
using the TV set as a monitor, and I really couldn't
read the text at 640x480 on it. And that was via a
composite video output.

http://en.wikipedia.org/wiki/File:S-video_spectrum.svg

Something I don't really understand about the above, is
what goes on with the HDMI option on some LCD TVs. An
LCD-TV seems to support standard computer monitor
resolutions on the VGA connector (like 1280x1024, 1024x768, 640x480
etc). Some don't offer native resolution, meaning they
resample everything effectively. I've downloaded a
couple LCD TV manuals in the past, and the modes on HDMI
seem to be ones like in the following picture. The
TV manual even says "HDMI not for computer" in the manual.
Now, I don't know how to interpret that in practical terms.
If the user hooks up HDMI, sets the computer resolution to
1280x1024, does that particular LCD TV freak out ? I've
read other manuals, where the HDMI input accepts both
computer resolutions and DVD player resolutions, and
in that case I'd be less concerned. Thus, if I was
blindfolded and put in a room with a computer and
an LCD TV, I'd reach for the VGA connector first...

http://en.wikipedia.org/wiki/File:Common_Video_Resolutions_2.svg

( http://en.wikipedia.org/wiki/List_of_common_resolutions )

HTH,
Paul

 

[John]

Very informative. Thank you.

Do you know any LCD TV with a DVI input? I don't think I've seen one.
About "HDMI not for computer", I've seen that as well. IIRC, Sony Bravia
manual says so. That confuses me too. My wild guess is we may be able to
connect PC to TV with an HDMI cable but the TV manufacturer doesn't support
it.

 

[John]

Last questions:
- What is the maximum HDMI/DVI cable length we can use?
- What's the max length on VGA cable?

The distance between my PC and TV is about 8 ft.

 

[+Bob+]

Last questions:
- What is the maximum HDMI/DVI cable length we can use?
- What's the max length on VGA cable?

The distance between my PC and TV is about 8 ft.

I don't know the engineering limits, but I've seen degradation on VGA
after 5 feet. We ended up installing a small booster amp.

 

[John]

I'm actually asking if 8-10 feet is close enough to use VGA connection.
Thanks.

 

[RalfG]

It depends on the signal strength from your video card and probably the
quality of the VGA cable as well. VGA extension cables exist and I've
used one in the past with no ill effects on the display quality.