If you do finish up getting that XGI Volari card, I see that it has a DVI Connector, (as will many other cards, - but not all.). Therefore, assuming your new 20 in LCD monitor is equipped with a DVI option, (most new flat panel monitors are!). Then I recommend getting a card with a DVI out, and using the DVI in preference to the 15-pin VGA. - The degree of improvement in picture quality will vary depending on various factors, ..... but DVI will always give a better/sharper image.
(.....Waits to be shot down on that last statement, - but I am convinced that it is a fact!)
ps, On the Newegg link given, the Asus V9400-X appears to be the only one showing a DVI connector. ....
That is the one I would be tempted to consider!