Q. Does DVI make a difference?
A. This depends very much on the panel in question. Some users of some panels say that switching between VGA and DVI makes NO difference on their screens. Notably users of the Samsung range (171T, 181T, 172X) have said it makes little or no difference, and has even been tested by users with 2 side by side. Other users of different panels swear it DOES make a difference. For example, I have personally seen the LG1710B in action in both modes, and the DVI was noticeably better quality and much sharper than the VGA. However the DVI connection on the LG I would rate as comparable to the VGA on some TFT’s without DVI at all, including the AOC LM720a. It seems logical that perhaps some manufacturers who build their screens without DVI spend more time perfecting the VGA connection as that is all they offer. Whereas companies who supply both connections sensibly would expect their users to use the DVI connection, as it is there, and so sacrifice quality of the VGA as the DVI can show off the full potential of their panel. Therefore screens without DVI tend to have a better VGA than those with DVI and in some cases a good VGA connection can be comparable in quality to a DVI connection.
Quality of the VGA connection is also related to the GFX card used. Most modern GFX cards have a good VGA output and this is important in image quality of the TFT. NVidia cards have been said to have a slightly better VGA output than the ATI cards, but as said, most new cards will give u a good quality output. Good output combined with a good VGA input on the screen will give u a good quality picture.
One other thing to note is that when using DVI connection, most TFT's lose the option of some of the on screen settings like contrast and brightness, so if u use DVI and u cant change them, some people have found the screens too bright. Software fixes are available for this though (inc Powerstrip etc)
RILOT: "I have non DVI TFT’s and the picture quality is exactly the same as my friends Samsung TFT that does have DVI. We tested them both together. Oddly though, when using the Samsung with VGA input the image quality was significantly worse......If you have a card with a decent 2d quality output it shouldn't make any difference whatsoever."
