I have an EVGA GeForce 9800 GT HDMI graphics card with an onboard HDMI connector (as well as the standard DVI and VGA connectors).

I am connecting my PC to my Sony HDTV via the card's HDMI connector.  Video works great (1920 x 1080p native) but I don't t get any audio through the HDMI connection.

I assumed initially that I needed an internal cable to connect SPDIF from my motherboard to the graphics card, but an EVGA support tech said no, that's not necessary on EVGA cards with an HDMI connector (it is needed on cards that connect HDMI using a DVI-HDMI adapter).  Ok, I'll take him at his word for now.

I went into the NVIDIA control panel and verified that card's connector is set to 'HDMI - HDTV (audio enabled)' and that the Digital Output Device (SPDIF) on the Windows Sound control panel is enabled and working fine.  But I still get no audio through the grapgic card's HDMI connection.

Is there something else I need to do to get audio working over my card's HDMI connector?  Do I in fact need to internally connect SPDIF from my motherboard to my graphics card?  (It does have a white 2-pin SPDIF connector on it.)

Thanks for any help or suggestions.

If the card is the EVGA 01G-P3-N988-TR then you need to hook up the SPDIF cable and set the Windows audio device to use the mobo internal SPDIF device. That's correct about what the white connector on the top of the card at the I/O bracket is for. Although those 9800 cards are called HDMI models, they do not have the onboard audio circuitry to process audio like some 2xxx series. They are still passthru SPDIF like every other 9800 model.

kenabi

the sound output should be set to 'NVIDIA HDMI ouput', and not S/PDIF, as they output to different things.

options for fixing can possibly include installing http://www.nvidia.com/obj...vista64_1.00.0.37.html (or google for the relevant version for your os (xp, vista 32, etc)

trying the spdif cable route

get the hdmi cable package and use the dvi -> hdmi adapter as well. (there's some issues with uncompressed audio only playing back in 2 channel on most audio chipsets, but there's work arounds to output to ac3 only, which would give full surround over the spdif connection)

bug tech support endlessly (not terribly advisable, but if it's the only option in a given case...)

cheers

Thanks the for help.

I have no NVIDIA HDMI ouput sound device, which seems to further confirm that I do indeed need the SPDIF cable.  EVGA support confirmed as much after replying to my inquiries yesterday and apologizing for claiming that my card didn't need the cable.  (I seem to have the only EVGA model with an HDMI connector that still requires the cable.)

Not sure I followed your comment re ac3.  I'm expecting that, once I get audio working over the card's HDMI connection (via a SPDIF cable), that I'll be able to output 5.1 audio through that HDMI connector (assuming a 5.1 audio source).  (My ASUS motherboard claims to support full 7.1 surround.) Is that not the case?

lardarse

prlaba 

I'm expecting that, once I get audio working over the card's HDMI connection (via a SPDIF cable), that I'll be able to output 5.1 audio through that HDMI connector (assuming a 5.1 audio source).  (My ASUS motherboard claims to support full 7.1 surround.) Is that not the case?

You will be able to pass what SPDIF passthru allows. It's constrained by SPDIF bandwidth standards even over an HDMI link. That will be 2-channel PCM or 5.1 AC3/Dolby and DTS (Compressed @ up to 640k/1536k bps). You will not be able to pass uncompressed 5.1 PCM or 7.1 PCM or any HD audio format (like those that exist on BluRay; DTS-HD, DD+, DD True HD, etc.)
 
Of course the device at the other end will also have to be able to decode them. TVs don't usually handle DTS.
 

Thanks for the good info.  I finally got around to connecting an internal SPDIF cable between my motherboard and my EVGA GeForce 9800 GT HDMI graphics card and confirmed that I now have working audio over my HDMI connector.  I verified that my HDTV could receive (and pass through to my receiver) both Dolby Digital 5.1 and DTS audio formats through the HDMI connector.  I don't have a Blu-ray drive in my PC, so I had no way to test soem of the newer 5.1 and 7.1 surround formats.

One question re your comment, "SPDIF cannot pass uncompressed 5.1 PCM or 7.1 PCM or any HD audio format."  The newer GeForce 2xx series HDMI cards, the ones with an onboard audio chip that eliminate the need for an SPDIF cable - do they also suffer this same restriction?  Or are they picking up audio in a different way?  Is a newer motherboard needed that provides something other than SPDIF for audio?

Thanks.