Video card for Dell 8300

[DurnIt]

I play Rise of Nations on my desktop, and recently I started getting gamefreeze. I upped my memory to 2.5 GB (from half a GB), but still freezes. I have viewed many different blogs/forum, and the GeForce 7300GT 512 MB DDR2 has been advised as a good card. I have an AGP 8x slot. I am also wanting to upgrade my PSU, that is another story. Any thoughts/advice on the card?