With the price vs performance on the cards available right now I see no reason you should continue to use that card if you plan on doing any more than web surfing, especially since youre getting into a new pc.
If you play new games or want to play new games you need to look for a better card. That card is below the minimum requirements of quite a few games. What new games it could run it would do so just barely on the lowest settings and resolutions. Well, at least for playable frame rates.
Of coarse, I assume that you plan on moving the card to the new computer when you get it. If not, you should probably hurry and get the new computer and see what card will come on it before you make a decision to upgrade.