HDMI vs. DVI video card

[fifreak3]

Looking at the video cards offered on Dell's XPS 420 desktop, none of them seem to have HDMI ports. Most (if not all) have 2 DVI connections though. I am considering the 2408wfp monitor, which has HDMI, Displayport, and 2 DVI ports. It seems that I would need a DVI to HDMI converter to use the HDMI port on the monitor, but would that provide any advantage over simply connecting the monitor to the computer with a DVI cable? Also, would utilzing both DVI ports (from the same video card to the same monitor) provide anything beyond what 1 DVI connection would, or is that to connect 2 different monitors to the same video card? Thanks.

I'm shooting for the best possible picture at 1920x1200 or 1920x1080.

 

[peterhuang913]

1 DVI connection is enough.

 

[Chankama]

Yeah, for your purposes, you only need one DVI out from the computer to a single DVI in on the monitor.

There is such a thing as dual-link DVI that you might've heard of. But, this is still within a "single" connector. If you look at the pins of your DVI cable, if its full of pins, then its dual-link - if about half the pins are missing, then its single link.

For WUXGA = 1920x1200 and 1080p = 1920x1080, you just need single-link DVI. For higher resolutions like WQXGA = 2560x1600 (I think), you need dual-link. The cutoff frequency between single and dual is around 165 MHz if I remember correctly. For the resolutions you need, you are in the < 165 MHz range - so single link is enough.

There "is" a very odd connector and a corresponding video standard that is not really commonly used that connects two separate single link cables between 2 output ports on the computer to two separate ports on the display. But, this connector is not worth talking about. I can't remember too much details about this anyways .

That being said, why does the computer and the display have two DVI ports each? On the computer, the two output ports can be used for dual displays. On the display side, the two input ports can be used for Main and PIP.

 

[CalcProgrammer1]

There's no point going DVI to HDMI on a monitor that you could just do DVI to DVI on. HDMI and DVI are practically the same thing, except that HDMI carries both audio and video while DVI is just video. HDMI introduced HDCP, but now you can have HDCP over a DVI connection too, so that doesn't affect which connection to use. HDMI and DVI are pretty much the same thing but with two different plugs...it really doesn't matter which one you use unless you plan on getting digital audio as well, in which you need to have an HDMI video card and HDMI monitor/HDTV. Right now I'm using a DVI w2007 monitor connected to my dv9700t's HDMI port using an HDMI to DVI cable.

 

[fifreak3]

OK, that all makes sense.
According the ATI's website, the cards I'm looking at, which ONLY have DVI ports and DO NOT have HDMI ones, are described as follows:

-HDMI with 5.1 surround sound audio
-HDMI output support
-Supports all display resolutions up to 1920x1080
-Integrated HD audio controller with multi-channel (5.1) AC3 support, enabling a plug-and-play cable-less audio solution

So does that mean that using a DVI to HDMI converter would also transmit audio to the monitor (which I could then output to external speakers with the monitors audio out)?

Also, is there such a thing as an "HDCP-equipped" DVI cable, or will my 5-year old DVI cable work just fine?

 

[Chankama]

So does that mean that using a DVI to HDMI converter would also transmit audio to the monitor (which I could then output to external speakers with the monitors audio out)?

You have to be careful when you read statements that say "DVI doesn't support audio". You have to make a distinction between the DVI physical interface and the DVI protocol. The DVI physical interface (i.e. pins) "should" be able to support audio as long as the HDMI protocol is used over it. HDMI does NOT use "separate" pins for audio. It uses "data" pins for both audio, video, and control multiplexed over time.. They are TMDS data lines.

If the HDMI protocol is run over DVI output and then through a converter goes to the HDMI input of the display, everything should be good - AS LONG AS the adapter drives out over the HDMI protocol. The ATI card probably does that.

Also, is there such a thing as an "HDCP-equipped" DVI cable, or will my 5-year old DVI cable work just fine?

Your 5-year old DVI cable should work just fine .. Ignore this marketing nonsense. One thing to be careful about is how well it handles high frequencies. If you are going to go WUXGA or 1080p, you will be exhausting the single-link frequency limit. If the "old" cable doesn't handle high frequencies well (even though they should), you might see some degradation. In any case, DVI cables are so cheap.. But, given the first question, I would imagine you want a DVI to HDMI cable. $10?

 

[CalcProgrammer1]

Yeah, DVI cables can carry audio (I have an HDMI->DVI male and HDMI->DVI female, if you connect the two DVI ends, the cable is a straight HDMI cable and carries both Audio and Video, so DVI connectors do carry audio when connected to HDMI).

You can have a video card that has DVI connectors output an HDMI/DVI video signal as well as an HDMI audio signal. The video signal on both is the same, but HDMI's protocol adds audio (well, it's optional, but it can have audio). Usually, monitors having DVI ports will not accept audio, but then again, this isn't 100%, as HDMI and DVI are almost completely interchangeable these days.

I wouldn't worry about the difference. If you have a video card with DVI ports that can output HDMI (audio), get a DVI male to HDMI male cable and use it to connect to an HDMI device (will get both audio and video). If you have a DVI monitor, get a DVI->DVI cable (if you don't already have one) and just use that (no audio).

 

[fifreak3]

So, perhaps with something like this Eforcity Black .6FT /2 Meter HDMI Male to DVI Male Cable - POTHHDMID2M1 - Buy.com, I would be just fine transferring both audio and video from the video card to the monitor?

 

[Preacher]

Take a L+R Aux in (3.5mm) to your Audio Card ?
DVI - Video.
Aux cable - Audio.

 

[Chankama]

So, perhaps with something like this Eforcity Black .6FT /2 Meter HDMI Male to DVI Male Cable - POTHHDMID2M1 - Buy.com, I would be just fine transferring both audio and video from the video card to the monitor?

Yeah that should work.

Take a L+R Aux in (3.5mm) to your Audio Card ?
DVI - Video.
Aux cable - Audio.

As we were discussing above, its possible to have audio over a DVI-HDMI (or even DVI-DVI) cable. The important thing is that the HDMI protocol is run over it.