Can you really tell a difference between DVI & VGA?

[Alexisonfire]

i know what vga is. I know what dvi is. I can't see a difference, can you?

 

[alpha88]

It makes a huge difference at 1920x1200.

 

[ProviaFan]

There is most certainly a noticeable different on my Samsung 213T (at 1600x1200, of course).

 

[aniruddha23]

found a very good post at pcmech

DVI is better than VGA for TFTs because they are digital and VGA is analog. A TFT displayes its picture digitally, pixel per pixel. Via DVI the panel gets data for each pixel, so the picture generated in the graphics card will match exact with the pixels on the panel itself.

Not so with VGA. First, the picture is generated digitally in the graphics card. Then it's converted to analog. In the TFT they will be converted again to digital (=> senseless twice conversion => quality loss), using the phase and the clock, and it'll be calculated which pixel should display what color. As the phase and clock can't be adjusted so precisely that a pixel of a picture generated by the graphics card will be displayed by the appropriate pixel on the panel. Means that the picture will be interpolated a little bit, which again means quality loss.

The electron cannons of the CRT need analog signals, that's why VGA is the best for CRTs and DVI would make no sense here.
For TFTs, DVI is the best. I won't get a TFT with no DVI.

 

[pkme2]

DVI is better than VGA, for TFTs because they are digital and VGA is analog. A TFT displays its picture digitally, pixel per pixel. Via DVI, the panel gets data for each pixel, so the picture generated in the graphics card will match exact with the pixels on the panel itself.

Not so with VGA. First, the picture is generated digitally in the graphics card. Then it's converted to analog. In the TFT they will be converted again to digital (=> senseless twice conversion => quality loss), using the phase and the clock, and it'll be calculated which pixel should display what color. As the phase and clock can't be adjusted so precisely that a pixel of a picture generated by the graphics card will be displayed by the appropriate pixel on the panel. Means that the picture will be interpolated a little bit, which again means quality loss.

aniruddha23 was faster.

 

[amheck]

in my system rig below, I noticed a substantial difference after I hooked up via DVI. the screen was noticably blurry when running via VGA

 

[dug777]

I've never noticed it (and neither have the people i asked if they could) on a nice Benq 17" LCD Off a 9600XT. Just as crisp & sharp.


You can on a 24" Dell however in some cases, and ironically the VGA pwns the DVI :laugh:

 

[ProviaFan]

Originally posted by: dug777
You can on a 24" Dell however in some cases, and ironically the VGA pwns the DVI :laugh:

I have no clue how that's possible. Can you show any pictures posted online to prove it, because given the current laws of physics, unless Dell really screwed something up with their DVI circuitry, that's not very likely.

 

[The Green Bean]

I can tell at 12*10

 

[Bobthelost]

It depends on the monitor i'm using, on my old Hitachi 17" it's very noticable, on the newer 19" Samsung it's not so. The problem isn't VGA, it's the converters in the monitor.

 

[Alexisonfire]

Thank you very much for the replies.

 

[Sonikku]

DVI does nothing over VGA when dealing with tubes. Be it computer monitor tubes or HDTV's. DVI only has an edge when dealing with fixed pixel displays, like LCD or DLP.

 

[firewolfsm]

It all depends on the size of the monitor, 19" and lower then you probably won't notice it.

 

[Machine350]

Originally posted by: firewolfsm
It all depends on the size of the monitor, 19" and lower then you probably won't notice it.

It's noticable on my 19". If you go to CompUSA, they usually have their display monitors hooked up via vga, and they all look blurry and just crappy in general. I don't see how they sell any monitors that way. With dvi, the picture looks crisp and clear.

 

[SynthDude2001]

Pretty big difference on my 2005FPW at 1680x1050, DVI is clearly better than VGA. VGA is probably fine for "small" LCD's (<1280x1024, and CRT's obviously), but I'd never use it on a large LCD.

 

[nullpointerus]

The difference is quite noticable on my 17" LCD, but then again I'm very picky about my display.

It will also depend somewhat on how crappy your video card's VGA output is.

 

[aka1nas]

VGA is far more sensitive to interference being an analog signal. I am actually running two 1907FPs here at work, one on DVI and one on VGA via KVM. The DVI-connected LCD is far sharper and has less banding issues. This is probably mostly due to the KVM FWIW, so take it with a grain of salt.

 

[dug777]

Originally posted by: ProviaFan

Originally posted by: dug777
You can on a 24" Dell however in some cases, and ironically the VGA pwns the DVI :laugh:

I have no clue how that's possible. Can you show any pictures posted online to prove it, because given the current laws of physics, unless Dell really screwed something up with their DVI circuitry, that's not very likely.

:laugh:

Read much on the gradient banding issues?

Seems Dell have done exactly that

 

[Fraggable]

I have a 19" LCD @ 1440X900 on VGA and a 23" LCD HDTV @ 1280X768 on DVI sitting side by side, and I can't see a difference between the two with respect to clarity and sharpness. Neither of those monitors are running at a massive resolution so maybe that's why.

 

[butt head]

Here's my 2c worth:

I am sitting in front of 2 Dell 2405 monitors (24", 1920 X 1200). One is connected via a DVi cable and another is connected with a vga cable. I can't speak for anyone else but I can tell you guys that the picture on both is identical and equally stunning. There is absolutely no difference in quality / detail / colour etc. I have swapped cables and switched one monitor from DVi to VGA etc and I can confirm that absolutely no one in my team (I'm a graphic designer, 20 years in the business) can tell the difference!!

I know that this should not be so, but it is.

BH

 

[dug777]

Originally posted by: butt head
Here's my 2c worth:

I am sitting in front of 2 Dell 2405 monitors (24", 1920 X 1200). One is connected via a DVi cable and another is connected with a vga cable. I can't speak for anyone else but I can tell you guys that the picture on both is identical and equally stunning. There is absolutely no difference in quality / detail / colour etc. I have swapped cables and switched one monitor from DVi to VGA etc and I can confirm that absolutely no one in my team (I'm a graphic designer, 20 years in the business) can tell the difference!!

I know that this should not be so, but it is.

BH

that's my experience as well.

I'd like to see a good comparison photo of a screen running DVI and teh same screen running VGA. Exactly the same screen details/lighting/camera position etc. My (admittedly cynical ) suspicion is that either the people who reckon they can see a difference are won over by teh placebo 'dvi is digital, therefore it must look better/different' mindset, or that their gfx card is doing a crappy analogue conversion.

I could even take a photo for you myself on my mates Benq 17" if you really want, but that's obviously only at 1280x1024

 

[nullpointerus]

My (admittedly cynical ) suspicion is that either the people who reckon they can see a difference are won over by teh placebo 'dvi is digital, therefore it must look better/different' mindset, or that their gfx card is doing a crappy analogue conversion.

Like I said, the latter is quite possible, but this implies that with DVI you don't have to worry. The fact that it is digital means that some cheapo, no-name video card will look just as well as a high end, brand-name card. With VGA it's more of a hit-or-miss, and I've seen my share of poor-quality integrated graphics in business PCs and laptops. I won't buy displays or cards without DVI.

 

[ProviaFan]

Originally posted by: dug777My (admittedly cynical ) suspicion is that either the people who reckon they can see a difference are won over by teh placebo 'dvi is digital, therefore it must look better/different' mindset, or that their gfx card is doing a crappy analogue conversion.

You're just wrong. On some / many LCDs, there is a difference, which is most certainly not a placebo affect as you try to insinuate. If I actually cared, I might get out my macro photography gear and dig up the HD15 cable that I haven't touched since upgrading to a DVI-capable video card a few days after I got my LCD, and prove that it can be so (no my video card doesn't suck, either - it works fine on a CRT at similar resolutions).

 

[imported_Seer]

There is a huge difference with the sharpness and clarity of text when switching to dvi from vga on my brothers 19" 1280x1024

 

[dug777]

No need to get all defensive there mate. I was simply going on my personal experience, and clearly i'm not at all alone as you can see from others in this thread.

I am intererested to see a pic side by side, identical conditions however, as i said.