Palmerq basically summed it up, but you have to realize it comes down the actual LCD. On some there really isn't a difference, on others there may be. Take a look at the specific panel before you buy it after having read some reviews and then decide. Remember, DVI-A, although DVI, is actually analog and not digital. DVI-D is digital.
<font color=white>XXXXXXXXXXXXXXXXXXXX
XXXXXXXXXXXXXXXXXXXX</font color=white>
<font color=green>XXXXXXXXXXXXXXXXXXXX
XXXXXXXXXXXXXXXXXXXX</font color=green>
<font color=red>XXXXXXXXXXXXXXXXXXXX
XXXXXXXXXXXXXXXXXXXX</font color=red>