I currently own and use the Nvidia 8500 GT graphics card with 512mb of video memory. I'm looking at the new Zotac 8800 GT with 512mb. The thing is, I don't know if there will be any significant difference between the two's preformance, considering they have the same amount of video RAM. I don't want to spend a fortune on a card with almost a gig of RAM, but I don't know how much of a difference there will be if I upgrade to this. Can anyone help me?