Would it be worth buying a new video card?

Here's my specs:

P4 2.6GHz

2 GB RAM

AGP 4x8x Bus



I want to buy a new video card but I'm wondering if it'd be like putting a chandelier in a haunted house? Moreover, would I even get a performance gain considering my other hardware is so old? I mainly play The Sims 3 if that helps.|||If you just play things like the sims or wow I'd say go for it but dont spend much over 100 because AGP is gone for good and if you ever get a new computer there is zero chance you can use it. But if you are going to play games like call of duty 4 or Crisis I'd say wait and save up for a whole new machine.