Your video card might be able to play the game Spore. I would try it before you buy a new video card.
If you want to buy a new card anyways, your going to need to give us some more details.
For example:
What other slot types do you have in your computer?
Eg: AGP, PCI, PCI-E, and then if its PCI, we need to know if its X1 PCI, or X16.
Check with your computer manufacturer to help us determine this.
Also provide us your computer manufacturer name, and your computers model number.