Choosing a mobo (VIA vs nVidia)

In the past couple of years I've assembled two computers based on the
A7V333 and more recently, one based on the A7V8X-X. All have had
nVidia video cards.

Now I need to assemble another one, and I am thinking of going with a
mobo with the nVidia chipset.

This new system, like my two A7V333 systems, won't be used for gaming.
It will be dual booted (WinXP and Linux RH) and when in WinXP will
sometimes be used for graphics intensive applications (Adobe
Illustrator, photo editing app, etc).

Will I see a major difference with the nVidia chipset? With an nVidia
video cart?

What is the difference between the A7N8X, A7N8X-X, A7N8X Delux, A7N8X-
E Deluxe? And while we're at it, what's the difference between all the
A7V models?

Is the nVidia chipset an "open standard"?

Thanks for any advice.

--
Brian P. Giroux