Many graphics cards on the market are designed with gaming usage in mind although they do offer good desktop application performance as well.
The GeForce 9500GT cards will give you decent 3D gaming and desktop application performance, the cards are able to support VGA connected monitors only.
Choose the Quadro FX 380 upgrades and you will get cards which can fully support both DVI and VGA monitors, they also run much quieter than the GeForce range and tend to have more stable drivers giving better overall performance.