Generally speaking, the more you spend on a graphics card, the more powerful it will be—the better the effects and the more frames you can push in AAA games. A $1,000 card isn't necessarily twice as good as a $500 card, but it'll definitely be a lot better.  However, there's such a thing as too much. If your computer is six or seven years old, the "bottleneck" of performance might be your processor or RAM, so spending four digits on a new card wouldn't be wise.