DVI -> HDMI issue

[brainfish]

Hi guys,

I have been searching around the net and can't seem to find a definitive answer to my problem.

I have a Nvidia GeForce 7300 SE/7200 GS graphics card in a Dell computer (4ish years old) and am trying to connect it up to the TV via a DVI -> HDMI cable. I can get video no problem but am having issues with the audio (no sound is coming through at all). Obviously I can use VGA with an audio cable and that is OK, but I would prefer to be able to use the DVI cable.

I know the cable is capable of transferring sound as from my laptop to my monitor (HDMI -> DVI) the sound works fine.

Anyone who is able to shed some light would be welcome.

Thanks,

[usually_quiet]

Audio isn't officially a part of the DVI specification. Although there are some graphics adapters that can provide audio from their DVI ports anyway from unused pins normally reserved for another purpose, not all video cards are capable of providing audio via DVI. That is what is probably happening here.

[brainfish]

OK, is there any way of finding out if my card in compatible or not? Or how much/where can I buy a card that is compatible?

[jagabo]

Although video is the same, audio in a DVI signal is multiplexed differently than audio in an HDMI signal. You'll need a DVI+SPDIF to HDMI converter box. And you'll need an SPDIF output on your computer and to have the audio directed there.

[usually_quiet]

OK, is there any way of finding out if my card in compatible or not? Or how much/where can I buy a card that is compatible?

If you want to research this for yourself, your best source of information is probably the manufacture's webpage for the video card, and not NVDIA's website, assuming you know which company that is. If you don't know the maker of the card, you will have to look for information at NVIDIA's website.

If you have to replace the video graphics adapter, do both your monitor and your TV have HDMI connections? If so, I recommend that you get a VGA card with HDMI out.

[jagabo]

If you're not a heavy duty gamer it's probably cheaper to get a graphics card with HDMI (with audio) out.

[usually_quiet]

There is one thing I forgot to mention in my earlier post. Since the DVI spec doesn't include audio, the VGA card's chip manufacturer decides which pins to use for audio and which part of the audio signal to assign to each pin.

The card manufacturer will sometimes provide a DVI to HDMI adapter/cable of some sort for the card if it can provide audio from a DVI port. The adapter for one card won't necessarily work with a different card and a generic DVI to HDMI cable that is not provided by the manufacturer may not work either.

[jagabo]

Forget trying to get audio over DVI. Use a converter like I mentioned earlier:

http://www.amazon.com/Audio-SPDIF-Toslink-Converter-Adapter/dp/B0015YYOQQ/

Or just get a graphics card with HDMI out. Pretty much all of them with an HDMI port support HDMI audio now.

[usually_quiet]

I need to make a correction. I had to review the HDMI and DVI pinouts for another discussion and I realized I given you the wrong information regarding how audio and video are carried for HDMI.

HDMI includes pins that provide functions that single link DVI-D doesn't, but HDMI transmits audio and video on the same pins. This means your DVI to HDMI cable would likely have provided audio if the Nvidia GeForce 7300 SE/7200 GS was sending an audio signal from its DVI port. If your current video card provides the option to use a DVI port for audio and video, there could be settings in NVIDIA's device drivers controlling audio output for the port. However, the only cards that I can recall seeing which are capable of using a DVI port for HDMI output with audio were made by ATI.

If you have to replace the Nvidia GeForce 7300 SE/7200 GS with a new card, finding one that provides an HDMI port is much easier than finding one that provides audio via one of its DVI ports.

[mh2360]

With older Nvidia cards, like the 9400GT that I used to own, you could get sound from the DVI port with a DVI->HDMI adapter, but you had to connect the card to the SPDIF header on the motherboard.

If there is a very small 2 pin socket on the card, it's likely to be the SPDIF input.

See the picture: