Quick easy question about VGA->DVI converters...

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thisismyusername

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I was reading the LCD faq before and came across this:

Quoted:
"Your video card produces an analog signal on the 15-pin cable, but the signal is converted back to digital by the signal processor on the LCD."

Does this mean that if your LCD only has VGA support, but your video card has a DVI port, you could buy a $5 VGA->DVI converter from radio shack and have a "true" (digital <-- --> digital) connection, since the monitor is going to convert that VGA plug into digital anyways (according to the FAQ).

Thanks. I have a feeling the answer is no (why would monitors bother coming with DVI ports), but who knows, it's worth asking heh.
 
If your vid card has DVI out, the four pins in the four-square config carry analog signals. The answer is yes it will work, but only in analog mode.
 
Hmm, so basically doing that wouldn't do anything?

I ask because I recently found out that it's impossible to do certain non-native resolution "tricks" without DVI. Like run a game at 640x480 full vertical, with black bars only on the sides in full screen (which would be the only way I could imagine playing a game -- spending $$ on an LCD that can't run it in full screen without a full horizontal stretch or requires you to play it in a fully encased black strip box isn't very nice).

Was hoping there was a way around that...
 
The DVI connector carries both digital and analog signal. When you attach a DVI to VGA converter (or vise versa) only the analog VGA signal carries through. So no matter what the LCD monitor will still have to convert that analog signal into it's own digital form for displaying.

Another interesting note is that since graphics cards of today still use a RAMDAC they do not support any fancy features that digital screens could potentially offer, such as segment addressing. The monitor actually has to convert the DVI signal to its own proprietary signal for use with the screen anyway. Of course this could be compared to a lossless compression scheme:

So in summary:
VGA is ANALOG and could be considered LOSSY.
DVI is DIGITAL and could be considered LOSSLESS.

Using a DVI to VGA connector is still LOSSY and there is no way to maintain that LOSSLESS data without the proper connectors and wire for both devices (GPU and LCD).
 
Oh, thanks for clearing that up. I'm curious though. I've been searching around all day and can't find an answer, ATI's site is useless, no answers on any hardware forums, etc...

Do you think in the near future, ATI's drivers will get an option to perform the same scaling options as DVI but on VGA, or is it a hardware limitation?

In all honesty, assuming the monitor I ordered comes in 1 piece, with no defects, I'm 99.9% sure I'll be very happy with it, other than the fact that I won't be able to play games at all, unless they support a wide screen format. Sadly that alone is enough to make me return it (I wouldn't even say I'm an avid gamer, it's just the only game that I do play requires a really low res, non-stretched screen, in addition to being full screen).
 
I don't know about your display, but my 2001FP has options for scaling even in analog mode. I can do 1:1 with a black frame around my active area, Fill, or Aspect.

I use Aspect on the analog input because even though my SGI can do UXGA, I lose a lot of GL features at that mode. If I use UXGA, I keep all the features and it's insanely fast even for a system from 96, but I end up with a 5:4 aspect ratio display on a 4:3 panel. The solution? Aspect. I fill the vertical while I get two .5" black bars on the sides. Sure, it's non-native, but it works fine.
 
It's this one:
http://www.newegg.com/Product/Product.asp?Item=N82E16824163130

The manufacturer's site really doesn't help much. I suppose I could e-mail them but by the time I get a response it'll probably arrive and I could see for myself.

I googled like no other, there's absolutely no info floating around that'll answer my question heh.

Your post brings me hope though. I didn't know you could do that with VGA.

"I fill the vertical while I get two .5" black bars on the sides"

^ That's exactly what I would like.

Are those options done with the on screen display, or drivers? If it's drivers, perhaps powerstrip or something could do it on any LCD (assuming the model I have doesn't support it in their drivers right out of the box).

Edit:
I just grabbed their manual from the site, and looked over the OSD functions. There doesn't seem to be a setting where you can adjust the aspect/etc.. The only setting that involves positioning the screen are for the horizontal and vertical screen placement (I guess similiar to a CRT, just moving the screen over a little bit).

Oh yeah I also use an ATI card (9600xt). In the driver setup, you can only modify the aspect/full screen/centered/etc. views if the connection is DVI. With VGA, those options don't even show up (on the CRT at least, I'm not sure with an LCD, but other people reported the same as my result -- the options just aren't there with VGA, even with an LCD).
 
I looked at the manual as well, it doesn't look like the monitor has any sort of scaling options and just stretches everything to the full size. Which is pretty typical for these widescreen 19" vga-only monitors.
 
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