What is the point of HDMI on an HTPC?

[Spuffin]

I have been looking to build an HTPC for quite some time and one of the things causing me to hold out is the need for HDCP so that I can view BluRay content. Now I could use a DVI or HDMI connection for this purpose but my TV - as with most - only has HDMI and VGA connections. So that's fine, now I just need to use HDMI. Pretty simple.

Except that I'd like to use a beefier video card so that I can run some 3D applications/games. Fine yet again! I'll just get myself a decent video card WITH HDMI! So simple!

Then there's the rub. The great unknown. I am assuming that my HDMI-out on the video card will ONLY carry video since the video card doesn't have an audio processor, and I have my doubts that it would pull the audio from anywhere. So this is where I really start to have questions.

1) Will the HDMI out on the video card pass audio as well? (my assumption is no)
2) If the HDMI is not passing audio - how do I use HDMI for video and something else for audio? I have not seen any settings on my TV to allow me to use this hybrid approach although admittedly, I haven't delved too far into that since it hasn't come up in my day to day usage. If this is true, it seems I'll have to watch everything with captions - but it sure will look pretty.

So it looks like my only options are
1) get a TV with a DVI connection
2) get a receiver with a hybrid HDMI for video and something else for audio
3) use VGA input with stereo cable and wait for someone to crack the BluRay encryption...

For those of you with experience with this - please share - and feel free to correct me if I've gotten anything wrong.

 

[lopri]

1) Yes
2) In that case, you select different audio output in Control Panel.

 

[Tempered81]

some cards have spdif input/passthrough for your hdmi cable but that results in tinny audio through your tv speakers

most people just want to send their audio out to the stero receiver components of their home theater via optical, dig coax, rca, dsub, minijack, etc.

if theres a newer simpler way, my advice just might show my age. heheh.

 

[Tempered81]

<dp>

 

[Spuffin]

Originally posted by: lopri
1) Yes
2) In that case, you select different audio output in Control Panel.

Lopri, are you speaking from experience/can you elaborate a little for #1?

Lets say I bought the EVGA 896-P3-1257-AR GeForce GTX 260 Core 216 which has an DVI -> HDMI connector and I use that to hook up to my HDTV. The video card is going to pull sound from onboard/soundcard?

That would be absolutely stellar if it does work this way but I have not seen any confirmation one way or the other that it would.

I appreciate your reply.

 

[aka1nas]

The onboard HDMI should natively pass audio. Might want to look into Hybrid SLI or Crossfire for this application, as then you can use the onboard for the HDMI hookup and keep power consumption down when you aren't gaming.

 

[LittleNemoNES]

Check out my thread on a very similar issue.

 

[Spuffin]

Originally posted by: gersson
Check out my thread on a very similar issue.

gersson: I read your thread and your "this cable" link doesn't work. Just making some assumptions I assume you did the following:
Hooked up SPDIF from internal motherboard connection to your video card - thus providing your video card with sound.
Bought the DVI -> HDMI adapter from whichever vendor you chose
Ran an HDMI cable from the adapter to your TV and it got your video *AND* sound.

Confirm?

 

[Modelworks]

Blame the MPAA for the screw up that is HDMI. The engineers wanted a signal dedicated just for sound. The MPAA stepped in and forced the sound to be encoded on the same stream as the video so that copy protection was easier to implement. I remember someone saying how they didn't realize pirating of movie soundtracks was a big business , but the good ol MPAA thought it was a threat, so now we have a nice closed proprietary system.

Engineers also wanted to put a thumb screw on each side of the cable end so the heavy cable weights would not put strain on the port. Did not happen because marketing said they wanted it to be plug and play and that thumbscrews would confuse the customer. So now we have sets that have broken hdmi ports due to strain from heavy cables.

 

[lopri]

I got a Radeon HD 3450 + Samsung 42" LCD to work via HDMI some time ago. The 3450 had an HDMI output built-in. For ATI cards with DVI ports, you'll have to use the supplied DVI-to-HDMI adapter if you want to get sound. Normal adapter will only carry video signal. Today's NV cards are supposed to carry 2 channel sound via HDMI (except their on-board GPUs which reportedly carry full 8 channel PCM) but I can't speak from experience about it.

 

[Zap]

Originally posted by: Spuffin
Lets say I bought the EVGA 896-P3-1257-AR GeForce GTX 260 Core 216 which has an DVI -> HDMI connector and I use that to hook up to my HDTV. The video card is going to pull sound from onboard/soundcard?

Yes, however it will require a special hookup to do that as it is unable to do so through the PCIe slot. If using onboard sound you will need a 2-wire connector to connect the SPDIF headers of the onboard sound to the SPDIF input of the graphics card. The picture here** has this wire (the really thin one). If your onboard sound does not have headers or you are using a separate sound card that doesn't have headers, then you need to source a different cable from either a mini-jack or coaxial SPDIF output to the same little plug on the graphics card. If you only have optical SPDIF, there are adapters but by then it is getting too complicated and you may as well find another way.

**Disclaimers apply, linked because I knew exactly where to look for a picture.

Originally posted by: lopri
Today's NV cards are supposed to carry 2 channel sound via HDMI (except their on-board GPUs which reportedly carry full 8 channel PCM) but I can't speak from experience about it.

This thread at avsforum seems to explain it a bit more.

 

[s44]

SPDIF won't carry uncompressed surround audio. HDMI will. However, Nvidia discrete cards, ATI cards before the HD4000 series, and ATI onboard chipsets will only carry SPDIF-equivalent audio streams over HDMI. For the full benefit of HDMI audio, you need either an ATI HD4000 series card (with HDMI adapter or built-in) or a Nvidia 8200/8300/9300/9400 integrated chipset with HDMI. (Both, by the way, have separate audio circuitry that operates *independently* of any Realtek or whatever chip you might also have.) If you have the Nvidia integrated chipset, you can use hybrid SLI to get full HDMI audio out of the onboard HDMI port while using the additional GPU power of one of the recent Nvidia cards.

 

[Spuffin]

I really appreciate everyone's replies. The links you've all provided (which also had links within them) were extremely informative in giving a current "state of affairs" in regards to HDMI and audio. It does appear that several cards supporting HDMI, even through an adapter, have an SPDIF connection and often include the SPDIF connector packaged with the video card. Things are finally looking up for my HTPC although further research will certainly be needed to ensure what I need is also what I want (or is close enough). This thread at AVS forum: http://www.avsforum.com/avs-vb/showthread.php?t=940972 is pretty top notch. Luckily I spotted it in someone's sig from the link Zap provided.

lastly, I have a buddy that may be building a comp later this month and I will be able to test this. Hopefully I remember to come back and post results in case anyone is interested since I had a helluva time finding information until starting this thread. Thanks again for the replies.

 

[Stoneburner]

Originally posted by: Spuffin
I really appreciate everyone's replies. The links you've all provided (which also had links within them) were extremely informative in giving a current "state of affairs" in regards to HDMI and audio. It does appear that several cards supporting HDMI, even through an adapter, have an SPDIF connection and often include the SPDIF connector packaged with the video card. Things are finally looking up for my HTPC although further research will certainly be needed to ensure what I need is also what I want (or is close enough). This thread at AVS forum: http://www.avsforum.com/avs-vb/showthread.php?t=940972 is pretty top notch. Luckily I spotted it in someone's sig from the link Zap provided.

lastly, I have a buddy that may be building a comp later this month and I will be able to test this. Hopefully I remember to come back and post results in case anyone is interested since I had a helluva time finding information until starting this thread. Thanks again for the replies.

That's a good thread i've been using in putting together my HTPC. Remember the updates are on page 85 or so.

Can you let us know, or let me know by PM what you decide to do? I'm leaning towards a radeon 4000 series card (the 4770 looks perfect for htpc).

 

[Wreckage]

I run DVI->HDMI on my TV and run optical to my receiver. Works like a charm.

My video card came with the DVI->HDMI adapter, but you can usually buy one for a few bucks.

 

[jiffylube1024]

Originally posted by: Wreckage
I run DVI->HDMI on my TV and run optical to my receiver. Works like a charm.

My video card came with the DVI->HDMI adapter, but you can usually buy one for a few bucks.

No HD audio that route, though. Optical can only carry Dobly Digital / DTS. No 5.1/7.1 LPCM, DTS HD (MA) or Dolby TrueHD.

I'm not sure if the OP cares about HD audio, but it's something to consider, and a big reason why you'd want to do audio and video over HDMI.

 

[Spuffin]

Well, it has been done. I helped a buddy of mine build his system with a GeForce GTX 260 which came with the spdif cable as well as a DVI->HDMI dongle. It was very simple; all we had to do was hook one end of the SPDIF cable to the appropriate connector on the motherboard and the other to the SPDIF connection on the video card. Lo and behold, we had video and sound coming out through one HDMI cable.

Unfortunately he does not have a surround sound setup so I cannot vouch for it's ability to provide the wide range of 5.1/7.1 options but it sounds crystal clear through the 2 speakers... Another note for those interested - he purchased a Logitech wireless(bluetooth) keyboard/mouse set that work beautifully. Don't listen to the crap you hear about people bad-mouthing wireless mice for gaming.

 

[Fox5]

Some nvidia cards have passthrough from the motherboard HD-audio.
Pretty much all ATI cards now have built in audio chips.

 

[kylebisme]

For surround you'd be limited to standard DD and DTS, missing out on the quality of HD audio, but for 2 channel that setup is as good as it gets.