Help please with HDMI, DVI, AGP, SPDIF soup…

06/17/2007 11:35:53 PM · #1

Iâ��m hoping someone will be able to help me figure out what I need to upgrade my PCs video card. It started out as a seemingly simple upgrade that has now got me going around in circles because Iâ��m just not up with all the latest gear. The big thing that has got me is getting sound to a HDMI TV input and trying to run two digital displays from a single AGP card.

This is what Iâ��ve got:

An old PC that Iâ��m perfectly happy with. It has an AGP 2 slot and spare PCI slots â�� I have no desire to upgrade anything other than the video card(s).

A LCD monitor running at 1920x1200 with VGA and DVI inputs. It supports reduced blanking and will run single DVI .

A LCD TV that runs 1920x1080 with VGA and HDMI inputs. It supports reduced blanking and will run single DVI .

A touch screen LCD at 1024x768 with VGA input.

At the moment everything is connected using VGA cables. I have an old PCI video card driving the touch screen and an AGP card driving either the big monitor or the TV. The AGP card has only one output, a VGA type. As a consequence if I want to use the TV for doing slideshows or watching video I have to switch the cables around and alter the video display resolution on the PC. All a pain in the butt, plus I get some image degradation trying to run such high resolutions over long VGA cables.

What I want to do:

Connect, and use, all three displays at once. Ideally I would like to connect the TV and big monitor using digital cables so as to get rid of the ghosting problems I have with VGA. Fortunately I donâ��t play games so I donâ��t need super duper 3D performance.

The problem:

Where do I get a AGP card that has two digital outputs? Lots of cards say dual output DVI but only have one connector. I know dual is used for ulta-high resolution, but is it also possible to â��splitâ�� dual DVI outputs to run two displays? I then assume I will need a DVI to HDMI adapter? But now I hit the big snag â�� HDMI sound. At the moment I use the VGA input and corresponding audio connectors on the TV. But the HDMI input has no corresponding audio connectors! So how do I get Audio into the HDMI input so I can watch video or listen to music with slideshows?

Much thanks for any help with this mess, Mike

06/17/2007 11:40:49 PM · #2

My card with Dual DVI, has two DVI ports and i uses a DVI to VGA adapter to use my LCD on it which doesn't have the DVI port.

HDMI is not used for audio, your gonna run a line from your soundcard to either the TV's IN or a home theatre system like i do. My card also has HDTV Component out which is how i connect to my TV.

I hope someone can be of more help.

06/17/2007 11:46:12 PM · #3

Also another note, when running dual displays typically only the primary display can view video. This is done to prevent copying via the second display output going to a recording device.

06/17/2007 11:47:50 PM · #4

Originally posted by RainMotorsports:

HDMI is not used for audio, your gonna run a line from your soundcard to either the TV's IN or a home theatre system like i do.

Thanks for the reply.
Oh.. I thought the HDMI carried both audio and sound because there aren't any audio inputs on my TV that activate when I select HDMI input. For the TVs VGA input there are audio connector which I currently have connected to my sound card. But if I select HDMI input those audio inputs turn off. All very confusing.

06/17/2007 11:49:08 PM · #5

Originally posted by RainMotorsports:

Also another note, when running dual displays typically only the primary display can view video. This is done to prevent copying via the second display output going to a recording device.

I didn't know that. I dont think it will affect anything I want to do, but thanks for the heads up.

Edit to clear something up that I may have been vague about. I don't just want the TV to mirror the monitor I want to use it as an extension of my desktop. Rather like I do now with the small touch screen monitor.

Message edited by author 2007-06-17 23:52:12.

Tamron SP AF 28-75mm f/2.8 XR Di for Canon

06/17/2007 11:49:17 PM · #6

Originally posted by zardoz:

Originally posted by RainMotorsports:

HDMI is not used for audio, your gonna run a line from your soundcard to either the TV's IN or a home theatre system like i do.

Thanks for the reply.
Oh.. I thought the HDMI carried both audio and sound because there aren't any audio inputs on my TV that activate when I select HDMI input. For the TVs VGA input there are audio connector which I currently have connected to my sound card. But if I select HDMI input those audio inputs turn off. All very confusing.

I could be wrong last time i checked HDMI is just for video, back when i had my other sound system i used an optical audio out to my stereo system. My father is using rca component cables for the moment.

As far as the dual display video problem thats been my experience on 3 systems their maybe a way around it let me know if u find out.

EDIT according to wikipedia it is for Audio and Video, but on my fathers setup he had to go another route odd, let me know what u find out.

Message edited by author 2007-06-17 23:50:50.

SamDoe1

Canon EOS-350D Rebel XT

06/17/2007 11:50:07 PM · #7

HDMI does carry both audio and video sources, but your video card (which would do the DVI->HDMI) does not put any sound through the cable since DVI doesn't carry sound. Anyway, this sounds like kind of a pickle but let me go through newegg quick and see what I can find for you. The other problem would be that AGP is old technology and the newer, better cards won't have an AGP interface.

Edit: Something like this would probably do well for you. You'd have to use the second card to drive the display like you do now, but this card will output dual DVI.

Edit again: This is a good DVI to HDMI adaptor that should do a good job. And that must be a pretty nice TV to have that resolution.

Message edited by author 2007-06-17 23:55:39.

06/17/2007 11:52:52 PM · #8

Originally posted by SamDoe1:

I was looking at wikipedia noticed it is for audio also.

ATi still makes all their cards on the AGP interface unlike nVidia which stopped at the 7600 GT. But all 3 major lines of ATi cards are offered on both AGP and PCI-E.

For 2d work and video it wont matter much and in 3D PCI-E does not use all of its capable bandwidth meaning it will one day just doesnt yet.

Problem with AGP is you wont find a board with 2 of them if you decide to upgrade your machine you can goe with dual PCI-E cards.

Message edited by author 2007-06-17 23:53:29.

06/18/2007 12:17:39 AM · #9

Thanks for those links Sam, looks like interesting stuff.
The TV is great I got it because of the resolution as I wanted it mainly for use with the computer. DPC looks great on it :) If I could just sort out this connection problem I'd be so happy.

I just found this thing on eBay link it takes a digital audio input and a DVI input and combines them into a HDMI out put. Its rather expensive though.
I also found this The description seems to suggest it has an audio output. I'm trying to find out more.

Tamron SP AF 28-75mm f/2.8 XR Di for Canon

06/18/2007 12:22:26 AM · #10

Originally posted by RainMotorsports:

Problem with AGP is you wont find a board with 2 of them if you decide to upgrade your machine you can goe with dual PCI-E cards.

I did wonder about this but I'm happy enough with the PC and I figure by the time I want to upgrade the whole thing will likely be obsolete anyway.

SamDoe1

Canon EOS-350D Rebel XT

06/18/2007 12:25:12 AM · #11

Originally posted by zardoz:

I just found this thing on eBay link it takes a digital audio input and a DVI input and combines them into a HDMI out put. Its rather expensive though.

With something like that, you're better off getting a nice sound card. It would end up being cheaper anyway.

Originally posted by zardoz:

I also found this The description seems to suggest it has an audio output. I'm trying to find out more.

Read reviews on that here, doesn't seem that people like it much.

Edit to add: I don't know if I'm understanding what you want to do correctly. Do you want to output audio as well as video to the TV and the monitor? If so a simple headphone cord with a splitter will do the trick. It won't be digital, but if you aren't porting that to a digital receiver it won't matter much. Just stick with the DVI and DVI->HDMI and you'll be fine. Also, it should have a corresponding audio connector, what kind of TV do you have? And if it has a DVI input on the back, that will for sure have a corresponding audio input.

Message edited by author 2007-06-18 00:30:44.

06/18/2007 12:30:43 AM · #12

You are right, they don't like it at all. But it is supposed to put sound through the HDMI connection even if it doesn't seem to work properly. So if there is one board that does it there must be others. I shall keep looking. And thanks again folks, I feel like I may be getting somewhere now.

Message edited by author 2007-06-18 02:09:36.

06/18/2007 12:39:25 AM · #13

Originally posted by SamDoe1:

Edit to add: I don't know if I'm understanding what you want to do correctly. Do you want to output audio as well as video to the TV and the monitor? If so a simple headphone cord with a splitter will do the trick. It won't be digital, but if you aren't porting that to a digital receiver it won't matter much. Just stick with the DVI and DVI->HDMI and you'll be fine. Also, it should have a corresponding audio connector, what kind of TV do you have? And if it has a DVI input on the back, that will for sure have a corresponding audio input.

I want to output audio through the TV. That is the only thing I want to do with the audio. The problem is the TV does not have any audio inputs that corespond to either of the HDMI inputs. It has the following connections:

2x HDMI
2x SCART
VGA + Audio
Component video + Audio
CVBS + Audio
S-Video + Audio
Line Out