Display Ports Question

Let me preface this by warning that it's going to be very vague; my new rig is only just in the planning stages right now, which means I haven't decided on any actual hardware just yet. Once the devs let us know the requirements for GR, that will change.

The situation is: I'm going to be hooking up the new rig to an HDTV to use as a monitor, and I just saw a potential snag. See, my current card (which is attached to a normal monitor) only has DVI output. I'm assuming this is going to be a trend for newer cards, and thus can't guarantee that the new rig will have the necessary HDMI output for use with the TV. However, said existing card did supply a DVI-to-VGA adaptor for those with older monitors.

So, the question is: will the DVI-quality output from the card still display in all its glory? Or does the VGA-style plug have some inherent limitation that will step image quality down no matter how pretty it should be?

Why would you use the VGA, when there are DVI to HDMI interface cables?

As to the resulting image quality, I couldnt' say.

See my Guides and Tutorials

Because I didn't know those adaptors existed?

Still it gives me something to look for. Anyone else know on the throughput question, though? My curiosity's still piqued, and I might need to know for plan B.

DVI = HDMI

Seriously, it's the same exact wiring, HDMI is just a more compact connector, and a couple extra wires for sound. You should be able to easily find a DVI<->HDMI adapter or cable. That's more likely to work and give good results with an HDTV then a VGA connection is.

Good luck!

EDIT: Some more technical details.

DVI and HDMI both include a digital video stream. VGA is of course, analog. DVI also includes in its specification (though it's optional) that around half the pins are analog VGA-style output. So that little DVI to VGA connector is just an adapter to let you connect your old analog monitor to the DVI port and still get a signal.

HDMI's digital part is identical to DVI, but it doesn't include the extra pins for an analog signal.

In practice, the signal degredation from going through an analog (VGA) step will vary based on your quality of cabling and the connectors, and how much interference you get. It will be more obvious with high resolutions than lower ones. You may also encounter phasing problems with the VGA cable if the HDTV has a fixed pixel grid, such as an LCD. You can work around that by using a special test pattern, and letting the TV re-sync to the signal, but in general it's easier and more bulletproof to just use the digital connection.

EDIT Again: More on the phasing issue. The test pattern is here:
http://www.techmind.org/lcd/phasing.html

If you go to that page on an LCD that's connected by an analog cable, you'll see lots of motion and jumping around.

It helps if you know what HDMI is; that being, it's DVI. Quite literally. Oh sure, DVI has extra pins for extra stuff (like VGA passthrough and a second set of links for really high resolutions) but they're electronically identical. A DVI to HDMI adaptor just re-routes some wires to make everything fit.

When the people who make TV cables came to draw up HDMI, they used DVI as a basis for it. They took out the VGA analog bits, removed the second set of links, made the cable thinner, designed a plug that could be blindly inserted (for when you fumble around behind the TV), and added copy protection to it.

Just remember, don't try to go VGA > DVI > HDMI, as I heard someone once did. DVI has separate cables for analog VGA and digital DVI/HDMI picture. This doesn't apply when you use a graphics card with a built-in DVI output, but it does mean you can't set up a bunch of adaptors for an older VGA graphics card. Analog doesn't magically turn into digital.

tl;dr, get a HDMI cable, DVI adaptor, HDMI adaptor or whatever. Your HDTV will work with it.

Here, DVI to HDMI dongles and cables.

I would just buy a TV that had DVI in. I find when I connect via an adaptor to an HDMI port from a DVI port I don't get as nice an image as when I connect to a DVI port. Unless of course the HDMI port on the TV is PC enabled.

So, to make sure I understand the answer (I'm a bit thick, so bear with me), there'd still be some degradation of the digital signal s it's fed through an analog port? (Specific details may vary, please make sure you live in a participating state, etc.)

Thanks muchly to Father Xmas for the converter link; assuming the card I end up getting doesn't have HDMI output, I'll just stick one of them onto the end and let it rip.

Thanks everyone!