DVI/HDMI (simple) question

ambro25

Having just got an ATI 9250 with DVI-out for my HTPC project, I now turn to interfacing with the HDTV, which has HDMI & component.

(i) Am I right in thinking that if I interface HTPC DVI to HDTV HDMI, I only get video and no sound through the interconnect?

(I understand DVI and HDMI are designed to carry video & audio, but I don't think a PC vid card with DVI also outputs audio... can it? )

(ii) And am I right in thinking that-
if the above is a yes,
and assuming the TV can't output audio from another source when on the 'HDMI channel'
I am better off using HTPC DVI to HDTV video component, and HTPC sound out to HDTV audio component?

n00b questions I know, but ya got to learn sometime...

christophicus

I am quite certain taht DVI does not carry sound. you will need to get the sound either from your sound card or teh motherboards onboard sound.

8T8

That is correct DVI does not carry sound just a digital or analogue video signal.

HDMI carries a digital video signal and digital audio signal.

When going from DVI->HDMI on a HDTV usually one of the scenarios below comes into effect.
The TV has auxiliary RCA audio inputs for the HDMI port.
The TV has a 3.5mm jack for audio input on the HDMI/DVI/VGA port.

If the TV has no auxiliary audio input you are faced with either an external sound system or acquire a graphics card with a built in HDMI output as these feature a digital SPDIF connection that will pipe the output from your sound card if it has an SPDIF output into the HDMI connection.

Failing all of the above just use the VGA port if present on your TV they always have a dedicated audio input for PC's, failing that now use component.

{RCA connectors are the typical red/white phono connectors you see on TV's, a 3.5mm jack is like the analogue sound output connections on your PC's sound card.}

ambro25

8T8 wrote:

The TV has auxiliary RCA audio inputs for the HDMI port.

Mmm... have a look at the upload. What do you think?

Are the 'IN' RCA inputs for both the HDMI and the component, or just for the component (the TV has specific 'HDMI', 'PC' and 'YPbPr' AV channels)?

(there's no VGA btw)

8T8

If the TV has no VGA why does it have a separate channel for PC & HDMI ?

Normally VGA is labelled as the PC channel, regardless what make TV is it ?

From the picture it is difficult to say the IN RCA ports look like they are for the component connection, do the OUT RCA ports feature a different connection or are they the same as the IN ports as I do not exactly understand why a HDTV would have RCA audio outputs ?

The fact they are placed next to the HDMI port which if it is PC compatible that is programmed with supported PC resolutions in it's EDID would suggest to me those RCA ports are possibly the auxiliary ones.

KdjaCL

Most Tvs have an audio cable IN beside the HDMI and DSUB connections. Run one from your sound cards line out to it and you have sound on the tv. Or position the PC speakers around the tv.


kdjac

ambro25

8T8 wrote:

If the TV has no VGA why does it have a separate channel for PC & HDMI ?

Dunno, beats me. Can't find anything about the 'PC' channel. The TV is a Sanyo CE27LC6-B. There's 3 SCARTs, composite down left side, HDMI and component and that's it. Positively no DSUB (VGA 15-pin, usually blue).

8T8 wrote:

the IN RCA ports look like they are for the component connection

Seemed that way to me too, which is why I asked for 2nd opinion

8T8 wrote:

do the OUT RCA ports feature a different connection or are they the same as the IN ports as I do not exactly understand why a HDTV would have RCA audio outputs ?

The RCA out are for TV sound OUT to any audio system (HIFI system/amp and whatnot). According to the manual they output (thru RCA) the same sound signal as is input to AV2 (AV2 is one of the SCARTs). So they are the 'AUX' ones.

KdjaCL wrote:

Most Tvs have an audio cable IN beside the HDMI and DSUB connections. Or position the PC speakers around the tv.
kdjac

Thx Kdjac, but no DSUB (VGA 15-pin) and initial query is because I want to avoid PC sepakers/use TV speakers.

So, solution looks like HTPC DVI video to TV component video, and HTPC sound card to TV component sound.

EDIT: I think I found what I need, but it's a bit ouchy on the wallet, so I'll be sticking to component for now.

8T8

Yeah it looks like component is the way to go however it is worth getting a DVI-HDMI cable as well just in case the audio is piped through the RCA audio ports for component video into HDMI as a few TV's can do that but the norm is to keep all the AV channels separate.

mossym

are you sure there isn't a menu somewhere on the tv that allows you to choose which video input those audio inputs are used with? be worth checking.

ambro25

Well, after all that...

Bit of a discussion at the week-end and I'll spare you the details, but the following is now in need of a good home:

Travla C137 (with 90W PSU and external brick adapter) silver, near-mint
VIA Epia M10000 Nehemiah with backplate
256MB DDR 2100
DVD/CDRW slim drive (ex-Dell, looks like D600 latitude, silver bezel but not quite same silver as case) with 50-p IDE to 40 pin 3.5" IDE adapter
PCI Radeon 9250 128MB VGA/compoTV/DVI, heatsink/passive cooling (1 week old)
3.5" 10GB IDE HDD
single PCI riser with 1 extension to fit Radeon horiz.

all fitted, running sweet and silent. Can be seen running vanilla MCE 2005 at time of sale, but for demo only. Sold without OS. Comes with following extras:

dual PCI riser with 1 spare extension
2.5" IDE to 40 pin 3.5" IDE adapter (not in use)
1.8" ZIF and CF typeI/II to 40 pin 3.5" IDE adapter (not in use)
3.5" FDD drive with ribbon (not in use)
MCE Remote and USB receiver

I thought I'd give ye guys a heads-up in here before I put it on adverts tonight. Would cost upwards of €400 at current prices, asking will most probably be at the €280 mark.